Pediatrics
Final Professional MBBS — Pediatrics. Complete question bank: Long Questions (10 marks) and Short Notes (5 marks) across all 15 systems, with clinical pearls, drug doses, staging tables, mnemonics and key-point recaps.
DEFINITION
Nephrotic syndrome is a clinical state resulting from heavy urinary protein loss, defined by a tetrad:
- Massive proteinuria — > 40 mg/m²/hour, or a urine protein:creatinine ratio > 2 mg/mg, or 3+/4+ on dipstick.
- Hypoalbuminaemia — serum albumin < 2.5 g/dL.
- Oedema.
- Hyperlipidaemia.
ETIOLOGY
- Idiopathic (~90%) — Minimal Change Disease (MCD) is by far the commonest (~85% in children) and is usually steroid-responsive; also focal segmental glomerulosclerosis (FSGS) and membranoproliferative GN.
- Congenital nephrotic syndrome (first 3 months; e.g. Finnish type).
- Secondary — Henoch-Schönlein purpura, SLE, infections (hepatitis B, malaria), drugs.
PATHOPHYSIOLOGY
Podocyte injury → increased glomerular capillary permeability → Massive proteinuria → Hypoalbuminaemia → fall in plasma oncotic pressure → Fluid shifts to interstitium → oedema → Liver increases lipoprotein synthesis → hyperlipidaemia
CLINICAL FEATURES
- Oedema — insidious; typically starts as periorbital puffiness (worse in the morning), then becomes generalised (anasarca) with ascites and pleural effusions.
- Frothy urine and decreased urine output; weight gain.
- Blood pressure is usually normal in MCD (hypertension/haematuria suggest a non-MCD cause).
- The child is usually 2–6 years old (MCD age group).
INVESTIGATIONS
- Urine — 3+/4+ protein; spot protein:creatinine ratio; microscopy (hyaline casts; RBCs suggest nephritic overlap).
- Blood — low albumin, high cholesterol; renal function; C3 (normal in MCD).
- Renal biopsy — NOT routine; reserved for atypical features (age < 1 or > 12 yr, gross haematuria, hypertension, low C3, renal failure) or steroid resistance.
DEFINITIONS (important for management)
- Remission — urine protein nil/trace for 3 consecutive days.
- Relapse — 3+/4+ proteinuria for 3 consecutive days.
- Frequent relapse — ≥ 2 relapses in 6 months (or ≥ 4 in a year); steroid-dependent — relapse on tapering or within 2 weeks of stopping steroids.
- Steroid-resistant — no remission despite 4–6 weeks of daily steroids.
MANAGEMENT
- Corticosteroids — prednisolone 2 mg/kg/day (60 mg/m²/day) for 6 weeks, then 1.5 mg/kg (40 mg/m²) on alternate days for 6 weeks, then taper (first episode).
- Supportive — salt restriction, diuretics for severe oedema, and IV albumin for refractory oedema/hypovolaemia.
- Infection prophylaxis — penicillin and pneumococcal vaccination (encapsulated-organism risk).
- Relapses/complex disease — steroid-sparing agents (levamisole, cyclophosphamide, calcineurin inhibitors, mycophenolate) for frequent-relapsing/steroid-dependent/steroid-resistant disease.
COMPLICATIONS
- Infections — spontaneous bacterial peritonitis (pneumococcal), cellulitis, pneumonia (loss of immunoglobulins).
- Thromboembolism — a hypercoagulable state (loss of antithrombin III).
- Hypovolaemia and acute kidney injury; hyperlipidaemia; and steroid toxicity.
EPIDEMIOLOGY
- Incidence ~2–7 per 100,000 children; commoner in boys.
- Minimal change disease peaks between 2 and 6 years of age.
NEPHROTIC vs NEPHRITIC SYNDROME
Feature Nephrotic Nephritic Core problem Heavy protein loss Glomerular inflammation Proteinuria Massive (3+/4+) Mild–moderate Haematuria Usually absent Present (RBC casts) Oedema Generalised (anasarca) Periorbital Blood pressure Usually normal Often raised MONITORING
- Home urine dipstick diary to detect relapse; daily weight during acute phase.
- Blood pressure, growth and steroid side-effects (cushingoid features, cataract, bone health) at each visit.
PROGNOSIS
Minimal change disease has an excellent long-term prognosis — most children are steroid-responsive and, although relapses are common, the majority 'outgrow' the tendency by adolescence with preserved kidney function. Steroid-resistant disease (often FSGS) carries a higher risk of progression to chronic kidney disease.
PATHOLOGY
In minimal change disease the glomeruli look normal on light microscopy; the only abnormality is effacement (fusion) of the podocyte foot processes on electron microscopy — hence the name. This explains its selective proteinuria and steroid responsiveness.
📝CLINICAL / APPLIED POINTS- MCD is the commonest cause and is steroid-responsive — so a first episode is treated with steroids WITHOUT a biopsy.
- Normal BP, normal C3 and no gross haematuria point to MCD; the opposite features prompt a biopsy.
- A child with nephrotic syndrome and sudden abdominal pain/fever = suspect spontaneous bacterial peritonitis.
- Watch for hypovolaemia (cold peripheries, tachycardia) despite oedema — treat with albumin, not aggressive diuresis.
- Teach families home urine dipstick monitoring to detect relapses early.
💊KEY DRUG DOSES (viva)- Prednisolone 2 mg/kg/day (60 mg/m²) × 6 wk → 1.5 mg/kg (40 mg/m²) alternate days × 6 wk.
- Furosemide 1–2 mg/kg + IV 20% albumin 0.5–1 g/kg for refractory oedema.
- Penicillin prophylaxis; steroid-sparing: levamisole, cyclophosphamide, tacrolimus, MMF.
🔑KEY POINTS TO REMEMBER- Tetrad: massive proteinuria, hypoalbuminaemia (< 2.5), oedema, hyperlipidaemia.
- Minimal Change Disease is commonest (~85%) and steroid-responsive.
- Periorbital → generalised oedema; BP & C3 usually normal in MCD.
- Treat first episode with prednisolone (no routine biopsy); add penicillin prophylaxis.
- Complications: peritonitis (pneumococcal), thrombosis, hypovolaemia, infections.
📚SOURCES: IAP/ISPN nephrotic syndrome guidelines; Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Acute post-streptococcal glomerulonephritis (APSGN) is an immune-complex-mediated glomerular inflammation occurring after infection with nephritogenic strains of Group A streptococcus. It is the commonest cause of acute nephritic syndrome in children.
ETIOLOGY & PATHOGENESIS
- Follows a streptococcal throat infection (after 1–2 weeks) or a skin infection/pyoderma (after 3–6 weeks).
- Immune complexes (streptococcal antigen + antibody) deposit in the glomeruli → complement activation and inflammation.
- This causes a proliferative glomerulonephritis with reduced glomerular filtration and salt/water retention.
CLINICAL FEATURES (acute nephritic syndrome)
- Haematuria — 'smoky', cola- or tea-coloured urine (the hallmark).
- Oedema — typically periorbital and facial, worse in the morning.
- Hypertension — from salt and water retention (may be significant).
- Oliguria and mild–moderate proteinuria.
- A preceding sore throat or skin infection in the history.
INVESTIGATIONS
- Urinalysis — haematuria with dysmorphic RBCs and RBC casts (glomerular origin), and proteinuria.
- Evidence of streptococcal infection — raised ASO titre (throat) or anti-DNase B (skin); throat/skin swab.
- Low C3 complement — a key finding that returns to normal within 6–8 weeks.
- Raised blood urea and creatinine; electrolytes.
💡CLINICAL PEARL: The classic triad to remember: a low C3 that normalises by 8 weeks, evidence of recent streptococcal infection, and an acute nephritic picture. A C3 that stays low beyond 8 weeks suggests another diagnosis (e.g. MPGN, lupus nephritis).MANAGEMENT
- Mainly supportive — salt and fluid restriction, and diuretics (furosemide) for oedema/hypertension.
- Antihypertensives (calcium-channel blockers/others) for significant hypertension.
- Penicillin to eradicate any residual streptococcal infection.
- Manage complications and monitor renal function, BP and urine output; rest during the acute phase.
COMPLICATIONS
- Hypertensive encephalopathy (headache, vomiting, seizures) — a hypertensive emergency.
- Acute pulmonary oedema / heart failure from fluid overload.
- Acute kidney injury (usually transient); electrolyte disturbances.
PROGNOSIS
The prognosis in children is excellent — APSGN is usually self-limiting. Urine output improves within days, C3 normalises by 6–8 weeks, and microscopic haematuria may persist for up to a year. Progression to chronic kidney disease is rare in children (unlike adults).
EPIDEMIOLOGY
- Commonest in children aged 5–12 years; more common where streptococcal skin infection is prevalent.
- Follows only certain 'nephritogenic' streptococcal strains.
DIFFERENTIAL DIAGNOSIS OF ACUTE NEPHRITIS
- IgA nephropathy (haematuria WITH the infection, normal C3), Henoch-Schönlein purpura nephritis (with rash).
- Lupus nephritis and membranoproliferative GN (persistently low C3) — considered if C3 stays low beyond 8 weeks.
MANAGEMENT OF HYPERTENSIVE EMERGENCY
- For hypertensive encephalopathy — controlled BP reduction with agents such as labetalol or nifedipine, plus a diuretic.
- Avoid abrupt, excessive falls in blood pressure; treat seizures.
MANAGEMENT OF FLUID OVERLOAD
Salt and fluid restriction with furosemide usually controls the circulatory congestion; occasionally, severe fluid overload with pulmonary oedema or refractory hyperkalaemia/uraemia needs short-term dialysis.
PATHOLOGY
The kidneys show a diffuse proliferative glomerulonephritis; immunofluorescence reveals granular deposits of IgG and C3 ('starry-sky' pattern), and electron microscopy shows subepithelial 'humps'.
NATURAL HISTORY
- Urine output and oedema improve within 1–2 weeks; blood pressure normalises early.
- Microscopic haematuria may persist for 6–12 months; C3 normalises by 6–8 weeks.
PREVENTION
Prompt treatment of streptococcal throat and skin infections and good skin hygiene reduce the incidence; there is no role for long-term penicillin prophylaxis after a single episode.
INDICATIONS FOR RENAL BIOPSY (atypical cases)
- Persistently low C3 beyond 8 weeks; heavy (nephrotic-range) proteinuria.
- Progressive renal failure or rapidly deteriorating function; anuria.
- Recurrence or an atypical course suggesting another glomerulonephritis.
📝CLINICAL / APPLIED POINTS- Nephritic = haematuria + hypertension + oedema + oliguria (contrast with the nephrotic 'protein-loss' picture).
- RBC casts and dysmorphic RBCs confirm a glomerular source of bleeding.
- A low C3 that recovers by 8 weeks is characteristic — a persistently low C3 needs a rethink.
- The dangerous early complications are hypertensive encephalopathy and pulmonary oedema — monitor BP closely.
- Prognosis is excellent in children; reassure the family.
💊KEY DRUG DOSES (viva)- Penicillin (to eradicate strep); furosemide 1–2 mg/kg for oedema/hypertension.
- Antihypertensives — nifedipine 0.25–0.5 mg/kg / labetalol for hypertensive emergency.
🔑KEY POINTS TO REMEMBER- Immune-complex nephritis after streptococcal throat (1–2 wk) or skin (3–6 wk) infection.
- Acute nephritic syndrome: haematuria, oedema, hypertension, oliguria.
- RBC casts; raised ASO/anti-DNase B; LOW C3 (normalises by 6–8 weeks).
- Supportive: salt/fluid restriction, diuretics, antihypertensives, penicillin.
- Excellent prognosis in children; watch for hypertensive encephalopathy & pulmonary oedema.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
A urinary tract infection (UTI) is significant bacterial growth in the urinary tract with compatible symptoms. It may involve the lower tract (cystitis) or the upper tract (pyelonephritis). UTIs are important in children because they may signal an underlying anomaly and can cause renal scarring.
ETIOLOGY
- Escherichia coli is the commonest organism (> 80%).
- Others — Klebsiella, Proteus (associated with stones), Enterococcus, Pseudomonas, and, in neonates, Group B streptococcus.
- Routes — mostly ascending; haematogenous in neonates.
CLINICAL FEATURES (age-dependent)
- Neonates & infants — non-specific: fever, poor feeding, vomiting, irritability, prolonged jaundice, failure to thrive, or sepsis. UTI must be excluded in any febrile infant without a focus.
- Older children — dysuria, frequency, urgency, suprapubic pain (cystitis); fever, loin pain and vomiting (pyelonephritis).
DIAGNOSIS
- Urine culture is the gold standard — significant growth depends on the collection method: clean-catch/midstream, catheter, or suprapubic aspiration (any growth) in young infants.
- Urinalysis — pyuria, positive nitrites and leukocyte esterase, and bacteria on microscopy support the diagnosis pending culture.
- Collect the sample before starting antibiotics.
VESICOURETERIC REFLUX (VUR)
- VUR is the retrograde flow of urine from the bladder up the ureter (± into the kidney), due to an incompetent vesicoureteric junction.
- It predisposes to pyelonephritis and renal scarring (reflux nephropathy), which can lead to hypertension and CKD.
- Graded I–V by severity (I = ureter only; V = gross dilatation and tortuosity with clubbed calyces).
IMAGING INVESTIGATIONS
Investigation Purpose Ultrasound (KUB) First-line — structural anomalies, hydronephrosis, bladder MCU (micturating cystourethrogram) Detects & grades VUR; shows posterior urethral valves DMSA scan Detects renal scarring / acute pyelonephritis MANAGEMENT
- Prompt antibiotics after sending culture — oral for older children with cystitis; IV antibiotics for young infants, toxic children or pyelonephritis, then oral.
- Ensure adequate hydration; treat constipation and voiding dysfunction.
- VUR — antibiotic prophylaxis for high-grade reflux/recurrent UTIs; surgery (reimplantation)/endoscopic correction for high-grade or breakthrough infections.
- Advise on hygiene, regular voiding and fluid intake.
COMPLICATIONS
- Renal scarring → hypertension, proteinuria and chronic kidney disease.
- Recurrent infections; urosepsis in young infants; renal/perinephric abscess.
RISK FACTORS
- Female sex; uncircumcised boys in infancy; poor perineal hygiene.
- Constipation and dysfunctional voiding; vesicoureteric reflux and obstructive uropathy.
- Incomplete bladder emptying; sexual activity in adolescents.
WHICH CHILDREN TO IMAGE
- All young children (< 2 years) with a first febrile UTI, and any child with an atypical or recurrent UTI.
- Ultrasound for all; MCU and DMSA guided by age, severity and ultrasound findings.
PREVENTION
- Treat constipation; encourage regular, complete voiding and good hydration.
- Perineal hygiene; prompt treatment of infections; antibiotic prophylaxis in selected high-grade VUR.
CLASSIFICATION
- Simple (lower) UTI — cystitis in an older child, systemically well.
- Complicated / atypical UTI — young infant, seriously ill, poor urine flow, raised creatinine, non-E. coli organism, or failure to respond in 48 hours.
- Recurrent UTI — ≥ 2 upper-tract, or ≥ 3 lower-tract, infections.
DURATION OF TREATMENT
- Lower UTI/cystitis — a short oral course (3–5 days).
- Pyelonephritis/upper UTI — 7–10 (up to 14) days; switch IV to oral once improving.
FOLLOW-UP
Ensure clinical resolution, complete imaging as indicated, and monitor blood pressure and growth in children with scarring or reflux; educate the family on early recognition of recurrences.
SPECIMEN COLLECTION — SIGNIFICANT BACTERIURIA
Method Significant growth Suprapubic aspiration Any growth of a pathogen Catheter sample ≥ 50,000 CFU/mL Clean-catch / midstream ≥ 100,000 CFU/mL A pure growth of a single organism with pyuria strongly supports the diagnosis; mixed growth usually indicates contamination.
📝CLINICAL / APPLIED POINTS- Always exclude UTI in a febrile infant with no obvious focus — the presentation is non-specific.
- Send urine culture BEFORE antibiotics; suprapubic aspiration is the cleanest sample in a sick infant.
- A confirmed UTI in a young child warrants imaging to look for VUR/obstruction and scarring.
- The aim of treatment/prophylaxis is to prevent renal scarring, hypertension and future CKD.
- Treat constipation and dysfunctional voiding — common, correctable contributors to recurrent UTI.
💊KEY DRUG DOSES (viva)- Oral: cefixime 8 mg/kg/day, co-amoxiclav, or nitrofurantoin (cystitis).
- IV (pyelonephritis/young infant): ampicillin + gentamicin 5–7.5 mg/kg/day, or ceftriaxone 50–75 mg/kg/day.
- Prophylaxis (VUR): cotrimoxazole/nitrofurantoin at ~⅓ therapeutic dose.
🔑KEY POINTS TO REMEMBER- UTI: lower (cystitis) vs upper (pyelonephritis); E. coli commonest.
- Infants present non-specifically (fever, poor feeding) — exclude UTI in any febrile infant.
- Urine culture is the gold standard; collect before antibiotics.
- VUR predisposes to pyelonephritis & scarring; image with USG, MCU, DMSA.
- Treat promptly; prophylaxis/surgery for high-grade VUR; scarring → hypertension/CKD.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics; ISPN/NICE UTI guidelines.DEFINITION
Acute kidney injury (AKI) is an abrupt (hours to days) decline in kidney function, causing retention of nitrogenous wastes and dysregulation of fluid, electrolyte and acid-base balance. It is defined by a rise in serum creatinine and/or a fall in urine output (KDIGO / pRIFLE criteria).
CLASSIFICATION BY CAUSE
Type Mechanism Examples Pre-renal (commonest) Reduced renal perfusion Dehydration (diarrhoea), shock, sepsis, blood loss Intrinsic (renal) Parenchymal injury Acute tubular necrosis, glomerulonephritis, HUS, nephrotoxins Post-renal Obstruction Posterior urethral valves, stones, tumour 💡CLINICAL PEARL: Pre-renal AKI from dehydration (e.g. diarrhoea) is the commonest cause in children — it is reversible if perfusion is restored early, but prolonged hypoperfusion progresses to established acute tubular necrosis.CLINICAL FEATURES
- Oliguria or anuria (urine output < 0.5–1 mL/kg/hour), though AKI can be non-oliguric.
- Features of the underlying cause (dehydration, sepsis, bloody diarrhoea → HUS, poor stream → obstruction).
- Features of complications — fluid overload (oedema, hypertension, pulmonary oedema), and uraemia (lethargy, vomiting).
INVESTIGATIONS
- Blood — rising urea & creatinine; electrolytes (hyperkalaemia, acidosis), calcium/phosphate.
- Urinalysis — casts (ATN/GN), blood/protein; fractional excretion of sodium (low in pre-renal, high in intrinsic).
- Ultrasound — kidney size and to exclude obstruction (hydronephrosis).
- Cause-specific tests (blood film & platelets for HUS, complement, cultures).
MANAGEMENT — General
- Treat the cause — restore circulation in pre-renal AKI (a fluid challenge if hypovolaemic), treat sepsis, relieve obstruction.
- Fluid balance — careful input/output; in established AKI restrict fluids to insensible losses + urine output.
- Stop/avoid nephrotoxic drugs and adjust drug doses; ensure adequate nutrition.
MANAGEMENT — Complications
- Hyperkalaemia — calcium gluconate (cardioprotection), insulin-dextrose, salbutamol, sodium bicarbonate, and potassium-binding resins.
- Metabolic acidosis — sodium bicarbonate if severe.
- Fluid overload/hypertension — fluid restriction and diuretics.
INDICATIONS FOR DIALYSIS (mnemonic — AEIOU)
- Acidosis (severe, refractory); Electrolytes (refractory hyperkalaemia).
- Intoxication (dialysable toxins); Overload (refractory fluid overload/pulmonary oedema).
- Uraemia (encephalopathy, pericarditis, severe symptoms).
PATHOPHYSIOLOGY & PHASES
Sustained hypoperfusion in pre-renal AKI progresses to acute tubular necrosis (ATN). Established ATN classically evolves through three phases:
- Oliguric phase — reduced urine output with rising wastes and the risk of fluid/electrolyte complications.
- Diuretic phase — recovering tubules produce large urine volumes (watch for dehydration and electrolyte loss).
- Recovery phase — gradual return of function.
MONITORING
- Strict input–output charting, daily weight, and serial electrolytes, creatinine and acid-base status.
- ECG monitoring in hyperkalaemia; blood pressure and fluid-status assessment.
PROGNOSIS
Pre-renal and post-renal AKI recover well if the cause is corrected early. Intrinsic AKI (ATN, HUS) may take longer, and severe or prolonged injury can leave residual chronic kidney disease — so follow-up of kidney function is important.
STAGING (KDIGO — by creatinine / urine output)
Stage Serum creatinine Urine output 1 1.5–1.9 × baseline < 0.5 mL/kg/h × 6–12 h 2 2.0–2.9 × baseline < 0.5 mL/kg/h × ≥ 12 h 3 ≥ 3 × baseline / on dialysis < 0.3 mL/kg/h × ≥ 24 h, or anuria ≥ 12 h SUPPORTIVE CARE & NUTRITION
- Provide adequate calories (limit catabolism); moderate protein, potassium and phosphate as needed.
- Treat infection; review and adjust all renally-excreted drugs.
PREVENTION
Most childhood AKI is preventable — early, adequate rehydration in diarrhoeal illness, prompt treatment of sepsis, cautious use of nephrotoxic drugs, and timely relief of obstruction.
📝CLINICAL / APPLIED POINTS- The first question in AKI: is it pre-renal (fix the perfusion) or is there obstruction (relieve it)?
- A fluid challenge helps confirm and treat pre-renal AKI — but avoid overload once AKI is established.
- Hyperkalaemia is the immediate life-threat — give calcium gluconate first to protect the heart.
- Post-diarrhoeal AKI with pallor and low platelets = think HUS.
- Remember the dialysis indications (AEIOU) and avoid nephrotoxic drugs.
💊KEY DRUG DOSES (viva)- Hyperkalaemia: calcium gluconate 10% 0.5 mL/kg IV (cardioprotection); insulin-dextrose; salbutamol neb; NaHCO₃; resin.
- Fluid challenge 10–20 mL/kg (pre-renal); furosemide for overload.
🔑KEY POINTS TO REMEMBER- AKI = abrupt fall in GFR (rise in creatinine / fall in urine output).
- Pre-renal (dehydration — commonest, reversible), intrinsic (ATN, GN, HUS), post-renal (obstruction).
- Complications: hyperkalaemia, acidosis, fluid overload, uraemia.
- Treat the cause + fluid/electrolyte management; calcium gluconate first for hyperkalaemia.
- Dialysis for AEIOU (acidosis, electrolytes, intoxication, overload, uraemia).
📚SOURCES: KDIGO AKI guidelines; Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Chronic kidney disease (CKD) is the presence of kidney damage or a reduced GFR (< 60 mL/min/1.73 m²) for ≥ 3 months. It is progressive and, in its end stage, requires renal replacement therapy.
CAUSES (differ from adults)
- Congenital anomalies of the kidney & urinary tract (CAKUT) are the commonest cause in children — renal dysplasia/hypoplasia, obstructive uropathy (posterior urethral valves), reflux nephropathy.
- Glomerular disease — chronic/steroid-resistant nephrotic syndrome, chronic glomerulonephritis.
- Hereditary — polycystic kidney disease, Alport syndrome; and HUS/systemic disease.
CLINICAL FEATURES
- Growth failure — a hallmark of childhood CKD (poor nutrition, acidosis, bone disease, hormonal factors).
- Anaemia (reduced erythropoietin), fatigue and pallor.
- Renal osteodystrophy (CKD-MBD) — bone pain, deformities, rickets-like changes.
- Hypertension and fluid overload; polyuria/nocturia early, oliguria late.
- Uraemic symptoms (anorexia, nausea, itching, encephalopathy) in advanced disease.
INVESTIGATIONS
- Estimated GFR (from serum creatinine/height); urea & creatinine; urinalysis (protein, blood).
- Electrolytes, calcium, phosphate, PTH, ALP, bicarbonate (metabolic bone disease/acidosis).
- Haemoglobin (anaemia); ultrasound (small/scarred or structurally abnormal kidneys); cause-specific tests.
MANAGEMENT — Slowing progression
- Treat the underlying cause and relieve any obstruction.
- Blood-pressure control and reduction of proteinuria with ACE inhibitors / ARBs.
- Avoid nephrotoxins; treat infections and dehydration promptly.
MANAGEMENT — Complications
- Anaemia — iron and erythropoietin.
- Renal bone disease — phosphate restriction, phosphate binders, and active vitamin D.
- Acidosis — oral bicarbonate; growth failure — optimise nutrition and use recombinant growth hormone.
- Manage hyperkalaemia and fluid balance.
RENAL REPLACEMENT THERAPY (end-stage)
- Dialysis — peritoneal dialysis (often preferred in small children) or haemodialysis.
- Renal transplantation — the treatment of choice for children with end-stage kidney disease (best growth and quality of life).
STAGING (by GFR)
Stage GFR (mL/min/1.73 m²) G1 ≥ 90 (with kidney damage) G2 60–89 G3 30–59 G4 15–29 G5 (kidney failure) < 15 / on dialysis NUTRITION & GROWTH
- Ensure adequate calories and protein for growth; correct acidosis (which impairs growth).
- Recombinant growth hormone for persistent growth failure; treat anaemia and bone disease.
- Involve a paediatric renal dietitian.
CARDIOVASCULAR & OTHER RISKS
- Hypertension and cardiovascular disease are major long-term risks — control BP aggressively.
- Manage electrolyte disturbances; immunise (including hepatitis B) and manage infections promptly.
PROGNOSIS
CKD in children is life-long; the goals are to slow progression, optimise growth and development, and prepare for renal replacement therapy. With good multidisciplinary care and, ultimately, transplantation, long-term survival and quality of life are good.
COMPLICATIONS OF CKD (summary)
- Growth failure and delayed puberty; anaemia; renal bone disease (CKD-MBD).
- Hypertension and cardiovascular disease (the major cause of long-term mortality).
- Electrolyte and acid-base disturbances; and, in end-stage disease, uraemic complications.
PSYCHOSOCIAL CARE & TRANSITION
Chronic illness affects schooling, development and family life; psychosocial support, adherence support, and a planned transition to adult services are important parts of care.
PREVENTION & EARLY DETECTION
Detecting and treating CAKUT, reflux and obstruction early, controlling blood pressure and proteinuria, and avoiding nephrotoxins can slow or prevent progression to end-stage disease.
INDICATIONS FOR REFERRAL TO A PAEDIATRIC NEPHROLOGIST
- Confirmed or suspected CKD (persistently abnormal GFR/urinalysis).
- Structural anomalies (CAKUT), significant proteinuria, or resistant hypertension.
- Growth failure, anaemia or bone disease attributable to kidney disease.
📝CLINICAL / APPLIED POINTS- In a child, CKD is usually congenital (CAKUT) — always image the urinary tract and look for obstruction/reflux.
- Growth failure is a defining feature — monitor height and treat aggressively (nutrition, acidosis, bone disease, GH).
- Control BP and proteinuria with ACE inhibitors to slow progression.
- Anticipate and treat anaemia (EPO/iron) and CKD-MBD (binders + active vitamin D).
- Transplantation gives the best outcome in end-stage disease — plan early.
🔑KEY POINTS TO REMEMBER- CKD = kidney damage or GFR < 60 for ≥ 3 months; progressive.
- CAKUT (congenital) is the commonest cause in children.
- Hallmarks: growth failure, anaemia, renal bone disease, hypertension.
- Slow progression: treat cause, control BP/proteinuria (ACE inhibitors), avoid nephrotoxins.
- Manage anaemia (EPO), bone disease, acidosis, growth; RRT = dialysis/transplant (transplant best).
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics; KDIGO CKD guidelines.DEFINITION
Haematuria is the presence of blood in the urine — gross (visible) or microscopic (≥ 5 RBCs per high-power field). The key clinical task is to distinguish a glomerular from a non-glomerular source.
GLOMERULAR vs NON-GLOMERULAR
Feature Glomerular Non-glomerular Urine colour Cola/smoky, brown Bright red, clots RBC morphology Dysmorphic Normal (isomorphic) RBC casts Present Absent Proteinuria Often significant Usually minimal CAUSES
- Glomerular — post-streptococcal GN, IgA nephropathy, Alport syndrome, HSP nephritis, lupus nephritis.
- Non-glomerular — UTI, urolithiasis (stones), trauma, tumours (Wilms), hypercalciuria, bleeding disorders, sickle-cell disease.
EVALUATION
- Confirm true haematuria (dipstick + microscopy; exclude myoglobin/food/drug discoloration).
- History & examination — recent infection, rash, oedema, hypertension, flank pain, family history.
- Urine microscopy (casts, morphology), protein; blood — renal function, C3, ASO; imaging (USG); referral for glomerular disease.
RED-FLAG FEATURES
- Hypertension, oedema, oliguria (glomerular disease); a flank mass (tumour); systemic features (rash, joint pain).
- Significant proteinuria alongside haematuria points to glomerular disease.
MANAGEMENT PRINCIPLE
Management is directed at the underlying cause — most isolated microscopic haematuria in a well child is benign and needs only monitoring, whereas glomerular disease, stones, or a mass requires specific evaluation and treatment.
KEY EXAM POINT
The single most useful step is urine microscopy: dysmorphic RBCs and RBC casts (± proteinuria) localise the bleeding to the glomerulus and change the whole line of investigation and referral.
INITIAL BEDSIDE STEPS
- Confirm blood on dipstick AND microscopy (exclude haemoglobinuria/myoglobinuria and food/drug colour).
- Check blood pressure and look for oedema, rash, and abdominal masses to triage urgently.
🔑KEY POINTS TO REMEMBER- Haematuria = gross or microscopic (≥ 5 RBCs/HPF).
- Dysmorphic RBCs + RBC casts + proteinuria = glomerular source.
- Glomerular: post-strep GN, IgA, Alport, HSP; non-glomerular: UTI, stones, trauma, tumour.
- Evaluate with microscopy, protein, renal function, C3, USG.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Wilms tumour (nephroblastoma) is the commonest primary renal malignancy of childhood, an embryonal tumour arising from primitive metanephric (kidney) tissue. It typically presents in children aged 2–5 years.
ASSOCIATIONS
- WAGR syndrome (Wilms, Aniridia, Genitourinary anomalies, Range of intellectual disability).
- Beckwith-Wiedemann syndrome and hemihypertrophy; Denys-Drash syndrome.
- Related to WT1 gene abnormalities.
CLINICAL FEATURES
- An asymptomatic abdominal mass — smooth, firm, and characteristically does not cross the midline (often found by a parent while bathing the child).
- Haematuria, hypertension (renin), abdominal pain, fever.
- The child is usually otherwise well.
⚠️DANGER / REMEMBER: Palpate the abdomen gently and minimally in a suspected Wilms tumour — vigorous palpation risks rupturing the friable capsule and disseminating the tumour.INVESTIGATIONS
- Ultrasound and CT abdomen — an intrarenal mass; assess the other kidney, IVC and lungs (metastases).
- Staging (I–V); histology after surgery guides risk.
MANAGEMENT & PROGNOSIS
- Multimodal — surgery (nephrectomy) + chemotherapy ± radiotherapy, according to stage and histology.
- Prognosis is good — overall survival is high (> 85–90%) with modern treatment.
DIFFERENTIAL DIAGNOSIS OF AN ABDOMINAL MASS
- Neuroblastoma — often crosses the midline, calcified, more ill child (contrast with Wilms).
- Hydronephrosis, polycystic kidney, and other abdominal tumours.
STAGING & FOLLOW-UP
Staged I–V based on operative and imaging findings; treatment intensity and prognosis depend on stage and histology (favourable vs anaplastic). Long-term follow-up monitors for relapse and treatment late-effects.
KEY EXAM POINT
The classic exam clue is a painless abdominal mass that does not cross the midline in a well 2–5-year-old — distinguish it from neuroblastoma (ill child, mass often crossing the midline), and avoid vigorous palpation.
STAGING (NWTS/COG)
Stage Extent I Limited to kidney, completely excised II Beyond kidney, completely excised III Residual non-haematogenous tumour in abdomen IV Haematogenous metastases (lung, liver) V Bilateral renal involvement HISTOLOGY
Favourable histology (most) vs anaplastic (unfavourable) histology — anaplasia predicts a poorer response and worse prognosis and guides treatment intensity.
🔑KEY POINTS TO REMEMBER- Commonest childhood renal malignancy (nephroblastoma), age 2–5 yr.
- Smooth abdominal mass that does NOT cross the midline; ± haematuria, hypertension.
- Associations: WAGR, Beckwith-Wiedemann, hemihypertrophy (WT1).
- Avoid vigorous palpation (rupture risk); USG/CT for diagnosis & staging.
- Surgery + chemotherapy ± radiotherapy; good prognosis.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Enuresis is the involuntary voiding of urine at an age when bladder control is expected (≥ 5 years). Nocturnal enuresis (bedwetting) is the commonest form. It is termed primary if the child has never been dry, and secondary if it recurs after ≥ 6 months of dryness.
ETIOLOGY
- Maturational delay and a strong genetic (familial) tendency.
- Reduced nocturnal ADH secretion; a small functional bladder capacity; deep sleep/arousal difficulty.
- Secondary causes to exclude — UTI, diabetes mellitus/insipidus, constipation, and psychological stress.
EVALUATION
- History (pattern, daytime symptoms, fluid intake, constipation, stressors) and examination.
- Urinalysis (to exclude UTI/glycosuria); most monosymptomatic cases need no further tests.
MANAGEMENT
- Reassurance and demystification — it is common, not the child's fault; avoid punishment.
- Behavioural — restrict evening fluids, void before bed, bladder training, and a star/reward chart.
- Enuresis alarm — the most effective long-term therapy.
- Desmopressin — useful for short-term needs (e.g. school camps) and older children.
TYPES
- Monosymptomatic — bedwetting alone (most cases).
- Non-monosymptomatic — with daytime symptoms (urgency, frequency, incontinence) → needs fuller evaluation.
PARENT COUNSELLING
- Emphasise it is common, self-limiting and NOT the child's fault; avoid blame or punishment.
- Most children become dry with time; combine reassurance with a chosen active therapy for motivated families.
WHEN TO INVESTIGATE FURTHER
- Daytime symptoms, secondary enuresis, or associated dysuria/polyuria/polydipsia.
- Suspicion of UTI, diabetes, constipation or a neurological cause — investigate accordingly.
KEY EXAM POINT
Enuresis at ≥ 5 years is common and usually a maturational issue — the two pillars are reassurance/behavioural measures and, for active treatment, the enuresis alarm (most effective) or desmopressin for short-term cover.
🔑KEY POINTS TO REMEMBER- Involuntary voiding at ≥ 5 years; nocturnal is commonest; primary vs secondary.
- Causes: maturational delay, genetics, low ADH, small bladder, deep sleep.
- Exclude UTI, diabetes and constipation (secondary causes).
- Reassure + behavioural measures; enuresis alarm is most effective; desmopressin for short-term.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Haemolytic uraemic syndrome (HUS) is a thrombotic microangiopathy defined by a triad of: microangiopathic haemolytic anaemia, thrombocytopenia, and acute kidney injury. It is a leading cause of AKI in young children.
TYPES & ETIOLOGY
- Typical (D+, diarrhoea-associated) HUS — the commonest; follows Shiga-toxin-producing infection (E. coli O157:H7, Shigella dysenteriae type 1).
- Atypical HUS — complement dysregulation (no diarrhoeal prodrome; often familial/recurrent).
PATHOGENESIS
Shiga toxin damages vascular endothelium → platelet-fibrin microthrombi in small vessels → mechanical destruction of red cells (schistocytes), consumption of platelets, and renal ischaemia.
CLINICAL FEATURES
- Typically 5–10 days after an episode of bloody diarrhoea.
- Pallor, lethargy, reduced urine output (oliguria/anuria), oedema and hypertension.
- Bleeding/petechiae (thrombocytopenia); may have CNS involvement (seizures).
INVESTIGATIONS & MANAGEMENT
- Blood — anaemia with schistocytes on film, thrombocytopenia, raised urea/creatinine, raised LDH.
- Mainly supportive — fluid & electrolyte management, control of hypertension, blood transfusion, and dialysis for AKI.
- Avoid antibiotics and anti-motility drugs in Shiga-toxin (typical) HUS; eculizumab for atypical HUS.
COMPLICATIONS
- Severe AKI needing dialysis; hypertension; fluid and electrolyte disturbances.
- CNS involvement (seizures, altered sensorium); rarely colitis complications.
PROGNOSIS
Typical (diarrhoea-associated) HUS usually recovers with supportive care and has a good prognosis, though some children are left with residual hypertension, proteinuria or reduced kidney function and need follow-up. Atypical HUS is more likely to relapse and progress.
KEY EXAM POINT
Remember the triad — haemolytic anaemia + thrombocytopenia + AKI — appearing about a week after bloody diarrhoea, and the crucial management point that antibiotics and anti-motility drugs are avoided in Shiga-toxin HUS.
🔑KEY POINTS TO REMEMBER- Triad: microangiopathic haemolytic anaemia + thrombocytopenia + AKI.
- Typical (D+) HUS follows Shiga-toxin E. coli O157 / Shigella diarrhoea.
- Schistocytes on the blood film; a leading cause of AKI in young children.
- Supportive care + dialysis; avoid antibiotics/anti-motility drugs in typical HUS.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Posterior urethral valves (PUV) are abnormal obstructing membranous folds in the posterior urethra, and are the commonest cause of congenital lower urinary tract obstruction in male infants. The obstruction causes back-pressure damage to the entire urinary tract.
CLINICAL FEATURES
- Antenatal — bilateral hydronephrosis, a distended bladder, and oligohydramnios on ultrasound (oligohydramnios → pulmonary hypoplasia).
- Newborn/infant — poor urinary stream/dribbling, a palpable bladder, failure to thrive, urinary tract infection, or renal failure.
- Older boys — voiding difficulty, incontinence, recurrent UTI.
INVESTIGATIONS
- Ultrasound — bilateral hydroureteronephrosis and a thick-walled, distended bladder.
- Micturating cystourethrogram (MCU) — the diagnostic test; shows a dilated posterior urethra above the valve (± VUR).
- Renal function and electrolytes.
MANAGEMENT
- Initial — bladder catheter drainage, and correction of fluid/electrolyte and acid-base disturbances; treat infection.
- Definitive — endoscopic valve ablation.
- Long-term follow-up for chronic kidney disease, bladder dysfunction and growth.
PATHOPHYSIOLOGY
The obstructing valves raise pressure throughout the urinary tract, causing bladder hypertrophy, hydroureteronephrosis and, antenatally, reduced urine output → oligohydramnios and pulmonary hypoplasia (a cause of neonatal respiratory difficulty).
PROGNOSIS
Outcome depends on the degree of renal damage already present at birth; despite valve ablation, a significant proportion develop chronic kidney disease and bladder dysfunction, so lifelong nephro-urological follow-up is essential.
KEY EXAM POINT
Consider PUV in any male infant with antenatal bilateral hydronephrosis or a poor urinary stream; the MCU showing a dilated posterior urethra clinches it, and early drainage plus valve ablation preserves as much kidney function as possible.
ASSOCIATED PROBLEMS
- Bladder dysfunction (thick-walled, poorly compliant bladder) often persists after valve ablation.
- Vesicoureteric reflux and recurrent UTIs; and, antenatally, pulmonary hypoplasia from oligohydramnios.
🔑KEY POINTS TO REMEMBER- PUV = commonest congenital lower urinary tract obstruction in boys.
- Antenatal: bilateral hydronephrosis, distended bladder, oligohydramnios.
- Postnatal: poor stream, palpable bladder, UTI, renal failure.
- MCU (dilated posterior urethra) is diagnostic.
- Catheter drainage → endoscopic valve ablation; long-term CKD risk.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Renal tubular acidosis (RTA) is a group of disorders in which the kidney fails to acidify the urine appropriately, producing a normal anion gap (hyperchloraemic) metabolic acidosis despite a relatively preserved GFR.
TYPES
Type Defect Key features Type 1 (distal) Impaired H⁺ secretion Hypokalaemia, nephrocalcinosis, rickets, failure to thrive; urine pH high Type 2 (proximal) Bicarbonate wasting Often part of Fanconi syndrome; hypokalaemia Type 4 Aldosterone deficiency/resistance Hyperkalaemia CLINICAL FEATURES
- Failure to thrive/growth failure, polyuria, polydipsia, and dehydration.
- Rickets/osteomalacia and nephrocalcinosis (distal RTA); muscle weakness (hypokalaemia).
DIAGNOSIS & MANAGEMENT
- Blood gas (normal anion gap acidosis), serum electrolytes, and urine pH.
- Alkali therapy — oral sodium bicarbonate or potassium citrate — to correct the acidosis; potassium supplementation as needed; treat the underlying cause.
WHEN TO SUSPECT RTA
- A child with failure to thrive plus a normal anion gap metabolic acidosis (and no diarrhoea).
- Unexplained rickets, nephrocalcinosis, polyuria or persistent hypokalaemia.
PRINCIPLES OF TREATMENT
Correcting the chronic acidosis with alkali therapy improves growth, bone health and the associated electrolyte disturbances; distal RTA usually needs smaller alkali doses than proximal RTA, and the underlying cause (e.g. Fanconi syndrome) is treated where possible.
KEY EXAM POINT
The hallmark is a normal anion gap (hyperchloraemic) metabolic acidosis in a child failing to thrive; distal (type 1) RTA classically also has hypokalaemia, nephrocalcinosis and rickets, and responds to alkali therapy.
CAUSES
- Primary/hereditary forms; and secondary to systemic disease.
- Distal RTA — nephrocalcinosis, autoimmune disease; proximal RTA — Fanconi syndrome (cystinosis, Wilson disease, drugs).
DIAGNOSTIC APPROACH
- Confirm a normal anion gap metabolic acidosis; then use serum potassium to narrow: low K → type 1/2, high K → type 4.
- Urine pH: inappropriately high (> 5.5) in distal (type 1) RTA despite acidosis.
- Urinary anion gap and a bicarbonate challenge help separate proximal from distal RTA.
🔑KEY POINTS TO REMEMBER- RTA = normal anion gap (hyperchloraemic) metabolic acidosis with preserved GFR.
- Type 1 (distal): hypokalaemia, nephrocalcinosis, rickets; Type 2 (proximal, Fanconi); Type 4 (hyperkalaemic).
- Presents with failure to thrive, polyuria and rickets.
- Treat with alkali (bicarbonate/citrate) ± potassium.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.DEFINITION
Cryptorchidism (undescended testis) is the failure of one or both testes to descend into the scrotum. It is common in preterm infants and is one of the commonest genitourinary anomalies in boys.
TYPES
- True undescended — arrested along the normal path of descent (intra-abdominal, inguinal).
- Ectopic — outside the normal path.
- Retractile — a normal testis pulled up by an active cremasteric reflex (not truly undescended).
- Ascending — a previously descended testis that later rises.
CLINICAL FEATURES
- An empty scrotum with a non-palpable or inguinal testis on examination.
- May be associated with an inguinal hernia.
COMPLICATIONS
- Infertility (impaired spermatogenesis, worse if bilateral).
- Increased risk of testicular malignancy.
- Torsion, trauma, associated hernia, and psychological effects.
MANAGEMENT
- Many testes descend spontaneously by 6 months of age — observe until then.
- Orchidopexy (surgical placement and fixation in the scrotum) is done between 6 and 18 months if it remains undescended.
- Early surgery reduces (though does not eliminate) the risks and allows monitoring of the testis.
RETRACTILE vs TRUE UNDESCENDED
A retractile testis can be gently coaxed into the scrotum and stays there briefly — it is a normal variant needing only observation, and must be distinguished from a truly undescended testis, which cannot be brought down.
WHY TIMING MATTERS
- Early orchidopexy (by 12–18 months) helps preserve fertility potential and places the testis where it can be examined.
- Surgery reduces but does not abolish the increased malignancy risk — so self-examination is advised later in life.
KEY EXAM POINT
The essentials: many testes descend by 6 months, so observe until then; if still undescended, do orchidopexy by 6–18 months to protect fertility and allow monitoring, remembering the lifelong (reduced but present) malignancy risk.
EXAMINATION TIP
Examine the child warm and relaxed (a cold room triggers the cremasteric reflex and mimics undescended testis); if the testis can be milked into the scrotum and stays, it is retractile and needs only observation.
🔑KEY POINTS TO REMEMBER- Failure of testicular descent; common in preterm infants.
- Types: true undescended, ectopic, retractile, ascending.
- Risks: infertility, testicular malignancy, torsion, hernia.
- Observe to 6 months; orchidopexy by 6–18 months if still undescended.
📚SOURCES: Ghai Essential Pediatrics; Nelson Textbook of Pediatrics.