Introduction<br />Synonyms: acute nephritis, <br /> acute nephritic syndrome<br />An immunologic mechanism: the result of an immune process that injures the glomeruli of the kidney.<br />Clinical features:<br />A sudden onset of hematuria, <br />Proteinuria,<br />Edema, <br />Oliguria and volume overload,<br />Hypertension, <br />Azotemia is another common but inconstant finding.<br />
Outline<br />Definition<br />Epidemiology<br />Etiology and Pathogenesis<br />Clinical Features<br />Complication<br />Investigation<br />Diagnosis<br />Differential Diagnosis<br />Treatment and Management<br />Prognosis<br />
Definition<br /> AGNthat follows an infection with a nephritogenic strain of group A beta hemolytic streptococci.<br /> The classic example of the acute nephriticsyndrome.<br />Nelson Textbook of Pediatrics, 7th Edition<br />
Etiology and Pathogenesis<br />The child gets gets throat or skin infection bynephritogenic strain of group A beta hemolytic streptococci - serotype 12 , 4 and 1<br />Antibodies to streptoccocus (egantistreptolysin O) are formed in his circulation<br />Antigen-antibody circulating immune complexes are subsequently deposited along the glomerular basement membrane (GBM). <br />
Typical Manifestation<br /> Develop acute nephritic syndrome 1–2 wk after an antecedent streptococcal pharyngitis or 3–6 wk after a streptococcal pyoderma.<br />Edema<br />75% of the patients<br />Face,periorbital area lowerextremities generalized (ascites, pleural effusions)<br />2. Proteinuria– usu. normalize after 4 weeks<br />3. Oliguria<br />school child < 400ml/day<br /> preschool child < 300ml/day<br /> infant & toddler < 200ml/day<br />
Typical Manifestation (2)<br />Gross hematuria(65% of patients)<br /> Smoky, tea-colored, cola-colored, or fresh bloody urine<br />Microscopical hematuria (almost all patients)<br /> The urine appears normal, but >3 RBCs/HP are found in centrifuged urine sediment examined microscopically.<br />Hypertension (50%) – mild to moderate, typically subsides promptly after diuresis<br />Nonspecific symptoms: <br /> Such as anorexia, vomiting, general malaise, lethargy, abdominal or flank pain, low-grade fever and weight gain.<br />
Clinical course<br />Spontaneous improvement typically begins within 1 wk with resolution of edema in 5-10 days and hypertension in 2-3 wk, but urinalysis may be abnormal (persistent microscopic hematuria) for a year.<br />
Complications in severe cases<br /><ul><li>Circulatory hypervolemia / Congestive heart failure
Not necessary if patient has clear cut acute nephritic syndrome</li></li></ul><li>Renal Biopsy<br /><ul><li>Patients whose clinical presentation, laboratory findings, or course is atypical.</li></ul>Delay resolution<br /> o oliguria > 2 weeks<br /> o Azotaemia > 3 weeks<br /> o Gross haematuria > 3 weeks<br /> o Persistent proteinuria > 6 months<br />Paediatric Protocols, 12th Edition<br />
Light microscopeNot specific for post streptococcal nephritis<br /><ul><li>Glomeruli appear enlarged and hypercellular.
Diffuse mesangial cell proliferation with an increase in mesangial matrix.
Polymorphonuclear leukocytes are common in glomeruli during the early stage of the disease.</li></li></ul><li>Electron microscope<br /><ul><li>Subepithelial electron-dense deposits or “humps” are present which are observed on the epithelial side of the glomerular basement membrane (GBM).
Gaps or discontinuities of GBM, which is likely indicative of proteinuria and hematuria.</li></li></ul><li>Immunofluorescence microscopy<br /><ul><li>Lumpy-bumpy deposits of immunoglobulin G and complement 3 along the capillary loops and within the mesangium.
It is helpful in the differential diagnosis of other entities that may mimic APSGN clinically, particularly IgA nephropathy.</li></li></ul><li>Diagnosis<br />Acute onset<br />Symptoms: edema, oliguria, dark urine, hypertension<br />Urinalysis: RBCs, protein, casts<br />Evidences of streptococcal infection:<br />Prodromes<br />Elavated serum titers of Abs to streptozymes(ASO)<br />Serum C3 - Reduced<br />
Treatment<br />Treatment of APSGN is largely that of supportive care. <br />Usually, patients undergo a spontaneous diuresis within 7 to 10 days after the onset of their illness - strict monitoring – nephrotic chart + fluid restriction until diuresis<br />Management is directed at treating the acute effects of renal insufficiency and hypertension <br />
Diuretics<br />Diet<br />Fluid restriction – during oliguric phase<br />Sodium restriction is necessary<br />Protein restriction is unnecessary<br />Antibiotics<br /> A 10-day course of systemic antibiotic therapy with penicillin V is recommended to limit the spread of the nephritogenic organisms.<br /> Antibiotic therapy does not affect the natural history of glomerulonephritis. <br />Paediatric Protocols, 12th Edition<br />
Treatment for complications<br />Significant asymptomatic hypertension<br />symptomatic, severe hypertension or hypertensive emergency / encephalopathy<br />Paediatric Protocols, 12th Edition<br />
Follow-up<br />• for at least 1 year.<br />• monitor BP at every visit<br />• do urinalysis and renal func on<br />to evaluate recovery.<br />• repeat C3 levels 6 weeks later if not already normalised by time of discharge<br />Paediatric Protocols, 12th Edition<br />
Prognosis<br />short term outcome: excellent, mortality <0.5%.<br />long term outcome: 1.8% of children develop chronic kidney disease<br />following post streptococcal AGN. These children should be referred to the paediatric nephrologists for further evaluation and management.<br />Paediatric Protocols, 12th Edition<br />