Approximately 50% of children with PSGN are asymptomatic and are discovered accidentally during routine urine analysis. The classic triad of glomerulonephritis includes hematuria, edema, and hypertension. Typically, patients give a history of a recent streptococcal infection such as pharyngitis, tonsillitis, or impetigo. However; some patients develop PSGN without experiencing symptoms of respiratory tract infection or pyoderma, which can be a diagnostic challenge.[9]

The most common presenting symptom is gross hematuria as it occurs in 30 to 50% of cases with acute PSGN; patients often describe their urine as smoky, tea-colored, cola-colored, or rusty. The hematuria can be described as postpharyngitic (hematuria seen after weeks of infection).

Renal involvement is common and is transient with recovery in 1-2 weeks. Less than half of the patients experience oliguria. Depending on the severity of renal involvement, signs, and symptoms suggestive of anuric renal failure or life-threatening acid-base imbalance, electrolyte abnormalities (especially hyperkalemia) and fluid overload would require RRT. About 60-80% of the patients experience high blood pressure which typically resolves in 10 days. [5]

The incidence of edema is seen in about 65-90% of the cases. Puffiness of the eyelids (periorbital edema) is typical for the nephritic syndrome. It is most prominent in the morning and tends to resolve at the end of the day. Generalized edema is also a common feature. Moreover, in severe cases, patients might experience respiratory distress as a result of pulmonary edema. They may experience other non-specific symptoms like anorexia, malaise, nausea, vomiting, etc.

PSGN should be suspected in all children with hypertension and heart failure, even in the absence of hematuria or a history of a preceding sore throat or pyoderma.

Laboratory investigations are the most useful in PSGN assessment.

• Evidence of a preceding streptococcal infection is determined by measuring anti-streptolysin titer (ASO), and anti-nicotinamide-adenine dinucleotidase (anti-NAD) which tend to rise following pharyngitis. Other antibodies such as anti-DNAse B and anti-hyaluronidase (AHase) are usually elevated after both pharyngitis and skin infections. ASO titer is the most frequently used test, while the most sensitive is the streptozyme test; which includes measuring the titers of all the antibodies mentioned above. ASO titers can be falsely low in patients treated with antibiotics for streptococcal infections. 

• Serum complement levels (C3) are usually low due to its consumption in the inflammatory reaction. Mostly, the decrease in C3 concentration occurs before serum ASO has risen.[5] Complement levels usually return to normal levels in 6-8 weeks.

• Urine analysis: shows macroscopic or microscopic hematuria, RBC casts, mild proteinuria. Only 5% of patients with PSGN have massive proteinuria that indicates nephrotic syndrome. White blood cell casts, hyaline, and cellular casts are usually present in the urine analysis.

• Renal Function Tests: Blood urea nitrogen (BUN) and serum creatinine typically elevate during the acute phase. These values usually return to normal later.

• In patients with heart failure and PSGN, NT-proBNP levels are elevated along with the findings of pulmonary congestion on the chest x-ray.

Renal biopsy is not recommended for diagnosing patients with PSGN and is performed only when other glomerular pathologies are suspected. Renal biopsy is indicated when:

• Progressive decline in the Renal function
• Anuric renal failure
• When there is no latent period between the acute glomerulonephritis and streptococcal infection
• If the complement levels are normal
• When there is no rise in antistreptococcal antibodies

Imaging studies:

• Ultrasonography: Kidneys are enlarged only in a few patients.
• The chest x-ray may show pulmonary congestion in patients with symptoms consistent with volume overload or heart failure. 

PSGN is a self-limiting condition in most cases, and thus only symptomatic treatment is needed. Supportive treatment aims at controlling the complications of volume overload such as hypertension and edema, which are prominent during the acute phase of the disease.[5]

Pharmacological therapy:

Antimicrobials: Patients with evidence of a streptococcal infection should receive a course of antibiotic therapy, and they may not prevent the development of PSGN.

Diuretics: Loop diuretics (furosemide) are preferred over thiazides (hydrochlorothiazide or chlorthalidone). The efficacy of thiazide diuretics is very minimal when GFR < 30 ml/min.

Antihypertensive medications: Blood pressure can be managed by restricting self and fluid intake along with diuretics are needed. In cases with uncontrolled blood pressure, the use of calcium channel blockers is recommended. The use of angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARBs) is recommended in patients with stable GFR and with near-normal potassium levels.

Immunosuppressive therapy: There’s no evidence that immune suppression is useful in patients with PSGN.[10]However, patients with progressive renal failure or the presence of crescents on the renal biopsy may warrant the use of corticosteroids.[11][11][11]

Dialysis: 

Dialysis is only performed to manage the acid-base balance, electrolyte abnormalities (especially hyperkalemia) and fluid management

General measures:

• Salt and water restriction to treat the edema.
• Bed rest and immobilization are recommendations in the first few days of the disease. 
• Throat cultures on the patient and family members are important.
• All affected members need to be treated with penicillin or erythromycin.

• IgA Nephropathy: usually occurs after an upper respiratory tract or gastrointestinal infection, but it differs from PSGN in the shorter latency period it takes to appear after the episode of infection. It can also be described as synpharyngitic hematuria- hematuria and infection coincide.
• Membranoproliferative glomerulonephritis: also presents with a nephritic picture and hypocomplementemia following respiratory tract infection. Complement levels take a longer time to return to normal than in PSGN or persistently low C3 levels.
• Lupus nephritis: sometimes PSGN presents with a picture similar to lupus nephritis. Laboratory testing for antibodies specific to each of the diseases can help in the diagnosis. Positive ANA, ds-DNA, cytopenia, and multi-organ involvement. 
• Nephrotic syndrome: 24-hour urine protein excretion is more than 3.5 gram/day along with hypoalbuminemia, edema, hypogammaglobulinemia and increased risk of thrombosis (due to loss of pro-coagulants).
• Henoch schonlein purpura (HSP): The typical presentation is palpable purpura, renal failure, gastrointestinal and musculoskeletal manifestations. Have normal complement levels. 
• Hemolytic uremic syndrome (HUS): Labs consistent with Hemolysis (schistocytes, LDH, reticulocyte count, indirect bilirubin), bloody diarrhea, thrombocytopenia, stool culture for Escherichia coil O157: H7
• ANCA: Have normal complement levels. 
• Goodpasture disease: Involves lung and kidneys. Have anti-glomerular basement antibody and normal complement levels. 

PSGN has an excellent prognosis especially in children with complete recovery usually occurring within 6 to 8 weeks. In adults, around 50% of the patients continue to have reduced renal function, hypertension, or persistent proteinuria.[12][13]

Death in adults is often secondary to heart failure and renal dysfunction. Studies show that in the long term some patients may continue to have abnormalities in urine, proteinuria, and hypertension.

Mortality during the acute phase of glomerulonephritis has been estimated at around 2 and 12 percent. It has been assumed that the renal changes found in the majority of patients who survived the initial acute attack would be qualitatively similar to those noted in the fatal cases, although little direct evidence existed to support this view[14]

During the acute phase, congestive heart failure and azotemia are likely complications that could be life-threatening. The delayed complications include chronic kidney disease and nephrotic syndrome.

• Nephrology

Avoidance of overcrowding and personal hygiene are important measures that patients should undertake to decrease the risk of catching streptococcal infections.

Patients with throat or skin infections should seek medical advice and get the proper antibiotic therapy if they receive confirmation of a bacterial infection.

Managing a case of PSGN requires cooperation between internists, nephrologists, infectious disease consultants, pharmacists, and nursing staff, functioning as an interprofessional team, to provide excellent care for their patients. PSGN patient’s fluid and salt intake, as well as urine output, should be carefully monitored by the team. The pharmacist should coordinate with the clinician to ensure that the patient is on no nephrotoxic medications and emphasize medication compliance if the patient has hypertension. The visiting nurse should encourage all close contacts and family members to undergo throat swabs to rule out an acute infection. The nurse should also weigh the patient to ensure that the edema is not worsening. Besides, renal function and potassium levels need to be closely monitored.

Consulting a nephrologist (or a pediatric nephrologist) must be sought in complicated cases. These patients need monitoring for fluid and electrolyte status at each visit. Close communication between interprofessional team members is vital to ensure good outcomes. [Level 5]

The prognosis in children is excellent but adults tend to have a protracted course with at least 30 to 50% developing renal dysfunction and hypertension.[15][16](Level V)