Pediatric IgA Nephropathy Clinical Presentation

Updated: Mar 20, 2017
  • Author: Mohammad Ilyas, MD, FAAP; Chief Editor: Craig B Langman, MD  more...
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Immunoglobulin A (IgA) nephropathy (IgAN) is characterized by recurrent episodes of macroscopic hematuria accompanied by upper respiratory tract infections or persistent asymptomatic microscopic hematuria with or without proteinuria. IgA nephropathy is frequently classified as primary (idiopathic) or secondary (associated with some other known condition).

Primary IgA nephropathy

Although the clinical presentation of IgA nephropathy varies from asymptomatic urinary abnormalities to acute renal failure, 5 different clinical syndromes are generally recognized.

The most common presentation (approximately 60-80%) of IgA nephropathy is asymptomatic microscopic urinary abnormalities with one or more episodes of intermittent gross hematuria. The recurrent macroscopic hematuria often associated with upper respiratory infection (viral pharyngitis) is traditionally regarded as the hallmark of childhood IgA nephropathy, compared with poststreptococcal glomerulonephritis (PSGN), in which hematuria usually occurs 1-2 weeks after infection. The hematuria is usually painless, but loin pain has been reported. Blood pressure may be within the reference range or elevated. Renal clearance function is within the reference range or reduced.

The second most common presentation (approximately 26%) is asymptomatic microscopic hematuria with or without mild proteinuria, hypertension, or reduced renal clearance function.

Acute nephritic presentation (approximately 12%) with heavy proteinuria, normal or low clearance function, and normal or high blood pressure is the third most common presentation.

Nephrotic syndrome may be the initial presentation in as many as 10% of patients.

Rarely, IgA nephrology may present as an acute crescentic glomerulonephritis with oliguria, edema, and hypertension.

Secondary IgA nephropathy

When renal mesangial IgA deposition occurs because of another specific clinical condition (secondary IgA nephrology), the history of that disease or signs and symptoms related to the primary condition may be present.



In the early stages of primary IgA nephropathy, no physical signs may be observed. However, early diagnosis might be suggested by a urinalysis that reveals microscopic hematuria with or without proteinuria.

Hypertension is infrequent, is mild to moderate, and is usually a late presentation of disease.

Edema due to nephrosis is reported in approximately 10% of patients.

If renal function is compromised at presentation, the patients may have signs of uremic syndrome, anemia, pallor, and lethargy.

If IgA nephrology is secondary to underlying disease, such Henoch-Schönlein purpura (HSP) or systemic lupus erythematosus (SLE), the signs and symptoms of that specific primary disease may be apparent.



The cause of primary IgA nephropathy is unknown. The conditions producing secondary mesangial IgA deposition include the following: