Granulomatous interstitial nephritis associated with atypical drug-induced hypersensitivity syndrome induced by carbamazepine.

We report the case of a 70-year-old female patient with granulomatous interstitial nephritis (GIN) induced by carbamazepine (CBZ). The patient had a 22-year history of bipolar disorder. Approximately 50 days before admission to our hospital, she was switched from valproic acid to 200 mg/day CBZ for mood swings. Forty days later, she presented with mild transient platelet depletion and liver dysfunction along with a C-reactive protein (CRP) level of 2.65 mg/dL. At that time, she discontinued CBZ without consulting the doctor. She subsequently developed high fever and a pruritic maculopapular rash. Laboratory tests revealed an elevated CRP level (11.98 mg/dL) and serum creatinine (sCr) of 1.6 mg/dL. Hence, she was admitted to our hospital, where she showed eosinophilia and immunoglobulin suppression. She was diagnosed with atypical drug-induced hypersensitivity syndrome (DIHS). All drugs prescribed by the previous doctor were discontinued. A lymphocyte transformation test showed CBZ positivity; a renal biopsy revealed many granulomatous lesions connected to arterioles, without angionecrotic findings. The patient had no history of allergic disorders or tuberculosis. Because of psychological instability, we treated her conservatively without steroid administration. She had a good recovery except for mild residual renal insufficiency (sCr, 1.0 mg/dL). Although granuloma formation has been observed in kidney biopsy specimens of rare cases with DIHS, no previous studies have reported on the relationship between arterioles and granuloma formation.

[Case of a focal segmental glomerulosclerosis collapsing variant associated with a hypertrophic column of Bertin].

A 59-year-old Japanese man admitted to our hospital complaining of anasarca, body weight gain, and elevation of blood pressure. Serum creatinine(Cre), albumin(Alb), cholesterol(chol), and urinary protein were 1.3 mg/dL, 2.5 g/dL, 527 mg/dL, and 10 g/gCr, respectively. An abdominal echography showed a renal mass, which was diagnosed to be a hypertrophic column of Bertin by enhanced CT. His serum Cre and Alb had worsened to 1.6 mg/dL and 1.7 g/dL, respectively, and a renal biopsy was performed. The results showed a segmental sclerotic lesion associated with hypertrophy and proliferation of podocytes in several glomeruli, hence we diagnosed a focal segmental glomerulosclerosis collapsing variant. After steroid pulse therapy and LDL apheresis, his serum Cre level had decreased to 1.1 mg/dL and the urinary protein level to 2.5 g/gCr. Patients with a focal segmental glomerulosclerosis collapsing variant are poor responders to standard therapies, and have a very poor prognosis. For this case, combined steroid pulse and LDL apheresis therapy was effective.

[Case of lupus vasculopathy associated with lupus nephritis class IV-G (A)].

Various renal vascular lesions are complicated with systemic lupus erythematosus (SLE), and are often overlooked in the actual renal biopsy specimen. We report a case of biopsy-proven lupus vasculopathy, with lupus nephritis class IV-G (A). She developed SLE at 15 years of age, and was treated with prednisolone(PSL) and cyclophosphamide (CTX). Sometimes she experienced a flare-up clinically or serologically, requiring a dose increase of oral PSL. At 40 years of age, she visited our hospital after discontinuation of hospital visits for about 4 months. Oral PSL at 30 mg per day was not effective for urinary abnormalities, increase of anti double-stranded DNA (ds-DNA) antibody titer and decrease in complement components. On admission she had hypertension (180/92 mmHg) and signs of microangiopathic hemolytic anemia. Renal biopsy findings showed the glomerular changes of lupus nephritis, WHO class IV-G (A), and lupus vasculopathy, which is marked luminal narrowing or total occlusion by abundant subendothelial accumulation of immunoglobulins and complement components. In addition to PSL, intravenous pulse CTX promptly achieved clinical remission. When lupus vasculopathy is complicated, CTX may be useful.