Niacin metabolite excretion in alcoholic pellagra and AIDS patients with and without diarrhea.

OBJECTIVE: Malnourished patients with the acquired immunodeficiency syndrome (AIDS) can develop pellagra-like manifestations such as dermatitis, diarrhea, and dementia; therefore, we tested the hypothesis that patients with AIDS and diarrhea would have niacin depletion. This study compared 24-h urine excretion of N1-methyl-nicotinamide (N1MN) among patients with pellagra and patients with AIDS who did and did not have diarrhea. METHODS: Three groups were studied: G1 (patients with AIDS and diarrhea, n = 5); G2 (patients with AIDS and no diarrhea, n = 7), and G3 (patients with alcoholic pellagra and without the human immunodeficiency virus, n = 8). Diarrhea was defined as the production of at least three liquid stools per day over 3 to 5 d. Studies included mucosal intestinal biopsy, malabsorption tests, detection of parasites in stool, and serum albumin measurements. Semiquantitative food-frequency questionnaire, anthropometry, and daily urinary N1MN excretion were also determined. Groups were matched in relation to age, sex, presence of parasites in stool, and intestinal absorption results. RESULTS: G1 had normal intestinal examination by light microscopy and no parasites in stools. G2 group showed lower levels of serum albumin (2.6 +/- 0.3 g/dL) when compared with G1 (3.4 +/- 0.3 g/dL) and G3 (3.1 +/- 0.7 g/dL). Except for patients with pellagra, groups met their energy requirements. Patients in G3 (0.013, 0.01-0.081 mg/dL) and G1 (0.062, 0.001-0.33 mg/dL) excreted smaller amounts of N1MN in urine than did those in G2 (0.63, 0.02-2.9 mg/dL). CONCLUSIONS: Patients with AIDS and diarrhea excreted less N1MN in urine than did those without diarrhea. These patients may have an impaired niacin nutritional status, possibly associated with increased metabolic needs.

Rituximab use in pediatric autoimmune diseases: four case reports.

Rituximab (RTX) is currently used in many diseases, but its efficacy and safety in juvenile systemic lupus erythematosus (SLEj) is still unknown. In this chapter we present four case reports of children treated with RTX: three SLE and one immune thrombocytopenic purpura (ITP). Two of the three SLEj patients had class IV lupus nephritis (LN) and hematologic manifestations (pancytopenia), both reaching complete recovery of blood counts and improvement of LN with RTX treatment. Our third SLE patient had a severe onset with generalized microangiopathic manifestations in association with antiphospholipid antibodies and has been in remission for almost 1 year after RTX. However, our fourth case, a patient with ITP and renal failure, was treated with RTX without either hematologic or renal response.