CASE 18 (August 2007)
An otherwise healthy 23-year-old woman presented with a 6-months history of episodic skin purpuric lesions in upper and lower extremities; lesions started and resolved spontaneously (in 1-7 days approximately). In the last episode (January 2007) she was admitted for study.
She had no history of other diseases; in the family history there is a cousin with only one spontaneosly resolving episode of pupura in her childhood. There is not family history of autoimmune or renal diseases.
On examination: palpable purpuric lesions until 5 mm in both legs; the lesions are not desquamative nor painful. There are not other alterations. She had not hypertension nor edema.
Laboratory tests: Renal ultrasound: normal; urinalysis: erythrocytes: 20 HPF, proteins: 1.04 g/24h, volume: 1,690 ml; serum creatinine: 0.7 mg/dl; BUN: 13 mg/dl; serum albumin: 4.4 g/L; Hb: 15 g/dl. Rheumatoid factor: negative; ANAs: negative; anti-Ro: 3.7 (0-15); anti-La 3.8 (0-15); anti-SM: 10.9 (0-15); anti RNP 2.6 (not increased); ANCAs: negative; C4: 19.8 (10-40) C3: 167 (90-180); anticardiolipin antibodies: Ig G 3.6 (0-10), Ig M 3.5 (0-7.0). HIV negative; hepatitis B and C tests: negative; VDRL no reactive.
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A renal biopsy was undertaken: 21 glomeruli, there are none sclerosed, in two there is segmental edocapillary proliferation (Figures 2 and 4); in one there is segmental sclerosis (Figure 5); in the remaining glomeruli there is normal appearance or mild mesangial proliferation.
See the images.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. Masson's trichrome stain, X400.
Figure 4. Masson's trichrome stain, X400.
Figure 5. PAS stain, X400.
Figure 6. Left and right: Direct immunofluorescence using antiserum to IgA, x400.
Immunofluorescence for IgG, IgM, C3, and C1q: Negative.
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