Anaphylactoid reactions associated with reuse of hollow-fiber hemodialyzers and ACE inhibitors.

From July 18 through November 27, 1989, 12 anaphylactoid reactions (ARs) occurred in 10 patients at a hemodialysis center in Virginia. One patient required hospitalization; no patients died. ARs occurred within minutes of initiating dialysis and were characterized by peripheral numbness and tingling, laryngeal edema or angioedema, facial or generalized sensation of warmth, and/or nausea or vomiting. All 12 ARs occurred with dialyzers that had been reprocessed with an automated reprocessing system. A cohort study, including all patients undergoing dialysis sessions on the six days when an AR occurred, showed that the patients who experienced ARs were significantly more likely than patients who did not to be treated with angiotensin-converting enzyme (ACE) inhibitors (7/10 vs. 3/33; relative risk = 7.9; 95% confidence interval = 2.5 to 25.2) and to have been exposed to reused dialyzers rather than to new dialyzers (12/70 sessions vs. 0/31; P = 0.016). In those sessions using a reused dialyzer, the mean number of dialyzer uses in case-sessions was significantly higher than for noncase-sessions (10.3 vs. 6.2; P = 0.016). After reuse of dialyzers was discontinued at the center, no further ARs occurred, despite the continued administration of ACE inhibitors. This is the first report of an outbreak of ARs associated exclusively with reused dialyzers. We hypothesize that interactions between a dialyzer that has been repeatedly reprocessed and reused, blood, and additional factors, such as ACE inhibitors, increased the risk of developing ARs.     

Evaluation of the Ca 1 monoclonal antibody in distinguishing oral squamous cell carcinoma from non-malignant or premalignant oral lesions

The Ca antigen has been reported to be present on the surface of malignant but not, with few exceptions, non-malignant cells. We investigated the potential usefulness of the monoclonal Ca 1 antibody in differentiating oral squamous cell carcinoma from non-malignant or premalignant oral neoplasms. Paraffin-embedded sections from 33 biopsy specimens of 12 hyperplastic and 21 neoplastic oral lesions were examined by immunohistochemical staining. Seven of the 33 specimens showed positive staining for Ca antigen. Fifteen of 21 specimens of oral squamous cell carcinoma were negative for Ca antigen, and one case of focal keratosis was positive. The results indicate that the use of the Ca 1 antibody to distinguish oral squamous cell carcinoma from non-malignant or premalignant oral lesions is highly unreliable.     

Clear-cell chondrosarcoma. An unusual case complicated by a microinfiltrative pattern of bone marrow involvement and postsurgical myositis ossificans

A case of clear-cell chondrosarcoma occurred in the proximal femur of a 32-year-old man. The tumor was complicated by a focus of myositis ossificans resulting from a previous intralesional biopsy. Histologic findings included an unusual marrow infiltration by the tumor. The patient was treated with wide resection and has no evidence of local recurrence or distant spread of disease 18 months later.     

Recurrent aphthous ulcers in association with HIV infection. Diagnosis and treatment.

Recurrent aphthous ulcers in patients with HIV infection can cause significant morbidity, which makes successful diagnosis and treatment imperative. We have found that the diagnostic paradigm for recurrent aphthous ulcers in HIV-seronegative patients, which is based on the ulcers' clinical appearance, location, absence of other ulcer-causing pathogens or pathogenic processes, and response to therapy, may be successfully applied to recurrent aphthous ulcers in HIV-infected patients. However, one must be alert for ulcers with uncommon causes as well as ulcers with common causes that have atypical clinical appearances that may mimic recurrent aphthous ulcers. The topical glucocorticoids, which are used to treat recurrent aphthous ulcers in HIV-seronegative patients, proved very effective in HIV-infected patients for treatment of herpetiform and minor ulcers and most major ulcers and were without notable side effects. A few severe cases of major recurrent aphthous ulcers required treatment with systemic prednisone, and some side effects were encountered.