Harvey J. Olander

Mesangial glomerulopathy and IgM rheumatoid factor in rheumatoid arthritis.

Hematuria and proteinuria in rheumatoid arthritis (RA) are commonly associated with drug therapy but occur independently of drugs, amyloid or urologic disorders. The latter occurrences suggest a primary renal lesion associated with RA. Review of reported renal biopsies identifies mesangial glomerulopathy as a common finding in RA patients without associated drug therapy and that it is frequently associated with hematuria in nonrheumatoid patients. Moreover, immunoglobulins have been shown to concentrate in the mesangium in experimental animals, suggesting that a functional response by the kidney mesangium to remove IgM rheumatoid factor (RF)-IgG complexes could lead to this mesangial lesion. We describe 3 patients with RA who had a mesangiopathy characterized by increased quantities of mesangial matrix and deposition of IgM without other lesions. Together, these observations suggest that: (1) mesangial glomerulopathy is common in RA; (2) removal of circulating RF-IgG complexes is a function of the mesangium and might produce this renal lesion; (3) mesangial glomerulopathy may be responsible for much of the hematuria observed in RA patients and, in many cases, may not be drug related and thus may not require discontinuing beneficial therapy.

The Migration of Hypoderma lineatum in the Brain of a Horse A Case Report and Review

A 2-year-old horse in California died following intermittent signs of ataxia and paralysis. A first stage larva of Hypoderma lineatum was found in a track of hemorrhagic malacia in the brain stem.

Bacillary Hemoglobinuria: Induction by Liver Biopsy in Naturally and Experimentally Infected Animals

An outbreak of bacillary hemoglobinuria was precipitated by liver biopsy of calves from an area in which the disease was enzootic. Using the strain of Clostridium hemolyticum recovered from this outbreak, calves, ewes, and rabbits were inoculated intravenously or orally with a toxin-free spore suspension. Subsequent liver biopsy precipitated the disease in these animals. The characteristic focus of liver necrosis was regularly reproduced and appeared to be of toxic rather than ischemic origin.