Structural and functional characteristics of the corpus callosum in schizophrenics, psychiatric controls, and normal controls. A magnetic resonance imaging and neuropsychological evaluation.

In 1986 Nasrallah and colleagues found that increased thickness of the corpus callosum may be specific to right-handed female schizophrenics. Male and female right-handed schizophrenics were compared with normal and psychiatric controls of comparable age, sex, education, and social class on measures of callosal thickness from a midsagittal magnetic resonance imaging cut and neuropsychological tests of interhemispheric transfer. The sex difference in anterior and posterior callosal thickness in normal controls was reversed in schizophrenics, with the corpus callosum being thicker in female schizophrenics and thinner in male schizophrenics. Similar findings were also observed in the psychiatric control group. These structural differences were not paralleled by evidence of impaired interhemispheric transfer on neuropsychological tasks. These results support the finding of sex-dependent callosal abnormalities in schizophrenia but indicate that these abnormalities may not be specific to this illness.

Tuberculous peritonitis.

Tuberculous peritonitis is an uncommon disorder and is often not considered on initial evaluation of ascites. A negative 5-TU PPD test, a normal chest roentgenogram, or a low level of ascitic fluid protein may erroneously direct attention away from tuberculosis. Failure to thoroughly evaluate nonmalignant exudative ascites, especially in alcoholics, is a common diagnostic pitfall. TB peritonitis should be considered in the differential diagnosis in every patient who presents with ascites, fever, and abdominal pain, particularly when alcoholism, a lung lesion, weight loss, or cirrhosis is also present. Percutaneous needle biopsy of peritoneum, followed by peritoneoscopy if necessary, may preclude the need for laparotomy. Antituberculous drugs, when conscientiously taken, afford a rapid response with a cure in most patients. Case material on four patients is presented.

Acute sarcoidosis occurring during the course of systemic lupus erythematosus.

A diagnosis of systemic lupus erythematosus (SLE) was established in a 54-year-old woman with a compatible history, as well as patchy alopecia, anemia, arthralgias, and a positive LE cell preparation. Sixteen months later bilateral hilar and mediastinal lymph nodes appeared on chest roentgenogram. Sarcoidosis was diagnosed when hypercalcemia and noninfectious, noncaseating epithelioid granulomas were found in the skin and liver. The sarcoidosis remitted with corticosteroid therapy, but slowly advancing renal failure ultimately resulted in the patient's death. We believe the concurrence of SLE and sarcoidosis had not been previously reported in the English literature. Immune mechanisms are discussed.

Effect of pH on the binding of theophylline to serum proteins.

The binding of theophylline to serum protein within the pH range of 7.0 to 7.8 was determined by equilibrium dialysis using serum from 8 healthy adult volunteers. The percentage of theophylline bound was independent of the total concentration of the drug, but was directly related to pH. Because changes in the free fraction of theophylline may alter the therapeutic response, toxic effects, and pharmacokinetics, any future studies of the pharmacology of theophylline should include assessment of the acid-base status of the patients and measurements of free as well as total theophylline concentrations.

Cardiac rhythm disturbances during fiberoptic bronchoscopy: a prospective study.

Twenty-six patients undergoing transnasal fiberoptic bronchoscopy (FOB) were electrocardiographically monitored for 12 hours before, during, and 12 hours after bronchoscopy. We measured arterial lidocaine concentrations during the procedure as well as arterial blood gases before and after the procedure. The incidence of total arrhythmias, including sinus tachycardia, during the control period was 69 percent; minor arrhythmias, 69 percent; and major arrhythmias, 8 percent. During FOB, the incidence of total and minor arrhythmias increased to 77 and 73 percent, respectively; however, the incidence of major arrhythmias decreased to 4 percent. Arterial lidocaine concentrations ranged widely, from 0.1 to 8.7 microgram per milliliter with a mean peak level of 5.0 +/- 0.6 microgram per milliliter, which was reached between 5 and 30 minutes after the insertion of the bronchoscope. We conclude that the incidence of cardiac arrhythmias, excluding sinus tachycardia, during FOB is low and that lidocaine anesthesia probably exerts a protective effect against the development of major arrhythmias during the procedure.

Influence of respiratory acidosis and alkalosis on volume of distribution of theophylline in dogs.

The volume of distribution of theophylline at nomal pH, and following induction of respiratory acidosis and alkalosis, was studied in four dogs in a three-way crossover design. Although serum half-lives of theophylline varied widely, and acidemia prolonged the time required for distribution equilibration, the volumes of distribution were almost identical for each of the three experimental conditions assuming one compartment pharmacokinetics apply.

Small airway disease: comparison of tests in young smokers versus nonsmokers.

A number of new tests for detection of small airway disease have been developed in the past several years. It is hoped that these will prove valuable as screening tests to detect those at risk of developing obstructive airway disease. We obtained data on the degree of discrimination of single breath nitrogen studies (CV/VC, CC/TLC, deltaN2/L), air-He studies (Vmax50), and the maximal midexpiratory flow (FEF25-75%) in detecting abnormalities in young smokers. Only the CV/VC and CC/TLC significantly separated smokers from nonsmokers, each revealing 20% abnormal values in smokers.