Angiocentric T-cell lymphoma of the tonsil: a case report.

We present a case of an angiocentric T-cell lymphoma (ACTL) occurring in a 31-year-old woman with the Acquired Immunodeficiency Syndrome (AIDS). This patient had oropharyngeal pain, a non-healing superficially ulcerated right tonsil, and no obvious tumor mass. Initial tonsillar biopsy revealed a subtle, non-specific, perivascular lymphocytic infiltrate subjacent to an ulcerated and inflamed mucosal lining. A benign, although atypical, inflammatory process was suspected. The distinctive features in this case include the relationship of ACTL to the Epstein-Barr Virus (EBV), which is usually related to B-cell lymphoproliferative disorders, the unique non-midline location of the lesion, and the relationship of ACTL to AIDS. ACTL appears to represent a unifying pathologic entity encompassing formerly described angioinvasive lymphoid lesions including polymorphic reticulosis, midline lethal granuloma, and lymphomatoid granulomatosis. We present these subtle histopathologic features to alert otolaryngologists who may encounter these cases, especially in AIDS patients who present extensive diagnostic possibilities. To the best of our knowledge, this is the first case report of ACTL involving the tonsil.

Coccidioides immitis presenting as a hyphal form in a ventriculoperitoneal shunt.

We report a case of meningitis in a 31-year-old man caused by Coccidioides immitis, where the organism was observed growing in the cerebrospinal fluid exclusively as hyphae. This unusual morphology was seen in fluid obtained from a ventriculoperitoneal shunt. Only C immitis was cultured. Its identity was confirmed by both DNA probes and standard culture techniques. To our knowledge this is the second report of C immitis taking a hyphal form in cerebrospinal fluid. Coccidioides immitis should be considered in the differential diagnosis when hyphal forms are seen in body fluids. The diagnosis can be hastened by using DNA probes, which enhance patient therapy and worker safety.

Listeria-associated pericarditis in an AIDS patient.

Listeria monocytogenes is a pathogenic, facultative intracellular gram-positive rod, generally seen in cell-mediated immunocompromised states. In acquired immunodeficiency syndrome (AIDS), it most commonly presents as bacteremia or meningitis. An association with pericarditis has not been described previously in this group of patients. This article describes a case of pericarditis secondary to listeriosis involving a focal pancarditis and necrosis of the A-V node with subsequent refractory ventricular tachyarrhythmias in an immunodeficient patient presenting with altered mental status. Infectious etiologies should be considered for "benign" appearing pericardial effusions in AIDS patients and the diagnosis of listeriosis excluded in the presence of "diphtheroid-like" organisms.

Doxorubicin interacts directly with skinned single skeletal muscle fibres.

The effect of doxorubicin, a highly effective anticancer agent, on the contractile apparatus of skinned single muscle fibres was tested in a concentration of 1 microM. Sarcomere length was set and held at 2 microns. Doxorubicin induced an increase in tension dependent on the Ca2+ concentration and time of incubation. The rise was up to 25% at [Ca2+] 40 microM. A parallel, small but significant shift of the calcium sensitivity curve, the relation between normalized tension and the negative logarithm of [Ca2+], the pCa, was observed. The results of this study suggest a direct interaction of doxorubicin with the actin myosin structure, possibly by an effect on myosin-ATP activity.

Pulmonary malacoplakia and Rhodococcus equi infection in a patient with AIDS.

We describe a case of pulmonary malacoplakia and Rhodococcus equi cavitary pneumonia in a patient with AIDS. The relationship between Rhodococcus equi, a rare bacterial human pathogen, and malacoplakia, an unusual type of chronic granulomatous inflammation, is discussed.

Serum theophylline assay by rate nephelometric inhibition immunoassay: a comparison with high-performance liquid chromatography.

The reliability of two clinical laboratory methods for assaying theophylline in serum is compared. Analysis of serum-based standards and 70 patient specimens by rate nephelometric inhibition immunoassay (NIIA) and by high-performance liquid chromatography (HPLC) demonstrates that both methods have comparable random analytical variation. The results indicate that NIIA is a reliable method for measuring serum theophylline and may serve as a practical alternative to the HPLC method.