Leprosy in five human immunodeficiency virus-infected patients.

We present five cases of leprosy in five human immunodeficiency virus-positive individuals. The patients were five men between the ages of 18 and 45 years. The five patients presented with skin lesions; three patients with hypopigmented skin lesions, one with skin macules and a history of leprosy, and one with papular lesions. In one patient, there was bilateral "claw hands." Histologically, two cases were categorized as lepromatous leprosy, two as borderline tuberculoid, and one as borderline lepromatous. Follow-up information obtained in the five patients showed one patient had died, and the remaining four patients were alive and receiving antileprosy treatment.

Morphologic differences between polyarteritis and Wegener's granulomatosis using light, electron and immunohistochemical techniques.

The differential diagnosis of renal biopsies of patients with polyarteritis nodosa (PAN) versus those with Wegener's granulomatosis (WG) is difficult because in both the morphologic expression is a focal proliferating and necrotizing glomerulonephritis (GN) with crescents. Twenty-nine biopsies of PAN and 29 of WG were studied by light, electron microscopy and immunohistochemistry. Whereas in PAN the dominent feature is severe focal fibrinoid necrosis of glomerular tufts, WG is characterized by destructive extracapillary GN with capsular breaks and periglomerulitis leading to complete glomerular destruction and replacement by a localized inflammatory exudate in the form of a granuloma. In PAN necrotizing arteritis is common (19 of 29), whereas only 1 of 29 cases of WG showed arteritis. Depending on the stage of the disease, various types of hematogenous cells can be seen in both. In general, the dominent cell type in PAN is polymorphonuclear cells (PMNs) with or without eosinophils, whereas in WG mononuclear cells dominate the picture. Monocytes and macrophages, including giant cells in the crescents, periglomerular infiltrates, and in the granulomas are seen, whereas in the interstitium, plasma cells predominate. The histologic ultrastructural and immunohistochemical findings in both groups will be discussed.

AIDS and the mycoses.

Profoundly immunoincompetent, patients with AIDS are vulnerable to myriad opportunistic bacterial, viral, protozoal, and fungal pathogens. Opportunistic infections in patients with AIDS are often severe, persistent, and relapsing despite appropriate therapy. Some infections are virtually untreatable. This article describes the mycotic complications in these patients.

Liesegang rings in tissue. How to distinguish Liesegang rings from the giant kidney worm, Dioctophyma renale.

Liesegang rings (LRs) are periodic precipitation zones from supersaturated solutions in colloidal systems. They are formed by a process that involves an interplay of diffusion, nucleation, flocculation or precipitation, and supersaturation. Examples include LRs of calcium carbonate in oölitic limestone (in nature), LRs of silver chromate in gelatin (in vitro), and LRs of glycoprotein in pulmonary corpora amylacea (in vivo). Here we describe LRs in lesions from 29 patients--mostly lesions of the kidney, synovium, conjunctiva, and eyelid. The LRs formed in cysts, or in fibrotic, inflamed, or necrotic tissue. The LRs in this study varied greatly in shape and size, measuring 7-800 microns. Special stains and energy-dispersive radiographic analysis or scanning electron microscopy revealed that some LRs contained calcium, iron (hemosiderin), silicon, and sulfur. Some pathologists have mistaken LRs for eggs, larvae, or adults of the giant kidney worm, Dioctophyma renale. D. renale is a large blood-red nematode that infects a variety of fish-eating mammals, especially mink. Fourteen documented infections of humans have been recorded, usually with adult worms expelled from the urethra. The adult worms are probably the largest helminth to parasitize humans. Eggs of D. renale are constant in size (60-80 microns X 39-47 microns), contain an embryo, and have characteristic sculpturing of the shell. Liesegang rings should not be mistaken for eggs, larvae, or adults of D. renale, or for any other helminth.