The HIV-positive dentist: balancing the rights of the health care worker and the patient.

We describe a hypothetical case of an HIV-positive dentist without cognitive impairment who uses proper infection control procedures. The dentist's physician notifies the medical officer of health without the dentist's consent. Although HIV-positive health care workers, including dentists, have been identified in the past, proven HIV transmission to patients is very rare. Most authorities recommend that an HIV-positive health care worker be monitored by an expert panel, which could then, if necessary, refer to the regulatory body to revoke or restrict the person's license to practice. Mandatory HIV testing is not required for health care workers because they generally do not pose a risk for infecting their patients; they are, however, ethically and legally obligated to report their HIV status to their profession's regulatory body.

AIDS-related risks in the health care setting: HIV testing of health care workers and patients.

Do patients and health care workers have the legal right to know each other's HIV status? Professor Flanagan argues that they do not. Given that with appropriate precautions the risk of transmitting HIV in the health care setting is extremely small and that the discriminatory consequences of HIV disclosure can be extremely high, it is suggested that the right of a patient or a health care worker not to disclose their HIV status must outweigh the other's "right to know."

Transrectal ultrasonography in stage A prostate cancer: detection of residual tumor after transurethral resection of prostate.

To evaluate the ability of transrectal ultrasonography to detect residual cancer in the prostate gland after transurethral resection in patients with stage A cancer, we studied 38 patients with stage A disease (11 stage A1 and 27 stage A2) in whom transrectal ultrasonography was done at least 3 weeks after resection. Each patient underwent radical prostatectomy, and residual cancer was present in 97% of the specimens (peripheral zone cancer in 95% and transition zone cancer in 61%). At sonography we identified hypoechoic areas suggestive of cancer in 10 patients (26%). In the pathological specimen residual cancer was present at the hypoechoic area in 8 of these cases (positive predictive value 80%). In a retrospective review of the sonograms we identified 25 hypoechoic lesions greater than 5 mm. in diameter, including 15 that corresponded to cancer in the radical prostatectomy specimens (positive predictive value 60%). Granulomas due to the transurethral resection were found in 92% of the radical prostatectomy specimens but none appeared hypoechoic on ultrasound. A total of 103 separate cancers was identified in the whole mount step sections of the radical prostatectomy specimens (2.7 cancers per patient). Of the 103 separate cancers 54 were less than 0.1 cc in volume and none of these could be identified in the retrospective review of the sonograms, 37 were 0.1 to 1.0 cc and 5 of these (14%) appeared hypoechoic, and 12 were greater than 1.0 cc and 10 of these (83%) appeared hypoechoic. Hypoechoic lesions greater than 5 mm. in diameter in the transition zone proved to be cancer in 47% of the cases, while 88% of similar lesions in the peripheral zone proved to be cancer. We conclude that suspicious-appearing hypoechoic lesions suggestive of cancer, whether in the peripheral zone or the transition zone, should be biopsied before expectant management of stage A prostate cancer is considered. Transrectal ultrasonography is useful for restaging after transurethral resection and for evaluating the extent of residual cancer in stages A1 and A2 prostate cancer.

Importance of purine nucleotide cycle to energy production in skeletal muscle.

The purpose of this study was to determine the role of the purine nucleotide cycle in aerobic energy production. Rats received either saline or 5-amino-4-imidazolecarboxamide riboside (AICAriboside), a precursor to an inhibitor of adenylosuccinate lyase (AICAR). Muscle tension was quantified during gastrocnemius stimulation, and muscle metabolite content was measured to obtain an estimate of the activity of the enzymes of the cycle. AICAriboside prevented the increase in synthetase and lyase activities observed in control animals during moderate (aerobic) stimulation, and was accompanied by marked muscle dysfunction. Although glycolytic energy production was not impaired in the AICAriboside-treated animals (lactate production occurred), total energy production did not meet energy demand. These results suggest that disruption of the purine nucleotide cycle impairs aerobic energy metabolism. Tetanic (anaerobic) stimulation produced more rapid fatigue in the AICAriboside-treated group. Total energy production was again impaired in the AICAriboside-treated animals, but lactate production was similar in both groups. These findings suggest the loss of the initial aerobic component of energy generation in tetanically stimulated muscle of AICAriboside-treated animals. The results of this study indicate that disruption of the purine nucleotide cycle at the level of the synthetase and lyase reactions is associated with skeletal muscle dysfunction, and suggest that the cycle plays an anapleurotic role in providing citric acid cycle intermediates that enhance aerobic energy production in contracting skeletal muscle.

Lumbosacral plexus stretch injury following the use of the modified lithotomy position.

The modified lithotomy position is used to provide simultaneous operative exposure to the abdomen and perineum. We report 3 lumbosacral plexus complications following use of this position. A mechanism involving stretch secondary to hyperabduction seems most likely. Electromyography is helpful in the diagnosis and the prognosis seems to be good.