CASE 38 (April 2009)
The patient is a 12-year-old girl. She presented unspecific general symptoms and macroscopic hematuria during two days. Symptoms and hematuria disappeared and urine returned to the normal appearance. A month later, again presenting with general malaise, now accompanied by abdominal pain with no a more specific location, and one day after an extensive skin rash with more notable involvement of the lower limbs (Figure 1). No necrotizing lesions. No organomegaly was palpated. No signs of gastrointestinal bleeding. No edema.
Blood pressure 110/60, heart rate: 72 X', temperature: 37.4 ºC.
Hemoglobin: 13.7 mg/dL, hematocrit: 43%, serum creatinine: 0.9 mg/dL. ANAs, ANCAs, Anti-DNA: negative. A, B, and C hepatitis: negative. Serum complement: normal levels. Proteinuria: 750 mg/24h, urine erythrocytes: 30-40 HPF; no casts.
What is your clinical diagnosis?
See the images.
Figure 1. Skin lesions.
Figure 2. H&E, X100.
Figure 3. H&E, X400.
Figure 4. Masson's trichrome stain, X400.
Figure 5. Masson's trichrome stain, X400.
Figure 6. Methenamine-silver stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Direct immunofluorescence using antiserum to IgA (both), X400.
Direct immunofluorescence for IgG, IgM, C3, and C1q: Negative.
What is your diagnosis?