Characterization of antibody and selection of alternative drug therapy in hydrochlorothiazide-induced immune hemolytic anemia

The authors report the clinical and laboratory findings of a patient who had severe immune hemolytic anemia due to hydrochlorothiazide (HCTZ). In this case, the HCTZ antibody reacted not only with other thiazide and thiazide-like drugs, but also with a chemically unrelated diuretic, ethacrynic acid. These results indicate that HCTZ antibody activity is not restricted solely to the thiazides and imply that therapy with any of the reactive drugs would be contraindicated for this patient. The serologic screening for drug reactivity may be useful for selecting alternative therapy for patients with drug-induced immune hemolytic anemia.     

In vitro bone-cell response to a capacitively coupled electrical field. The role of field strength, pulse pattern, and duty cycle.

Newborn rat calvarial bone cells were grown to confluence and subjected to a matrix of sine wave 60-kHz capacitively coupled electrical signals of various field strengths, pulse-burst patterns, and duty cycles. Both [3H] thymidine incorporation into DNA and alkaline phosphatase activity were evaluated in field strengths ranging from 0.0001 to 20 mV/cm, with pulse-burst patterns ranging from continuous to 5 milliseconds ON/495 milliseconds OFF, with daily duty cycles ranging from 0.25% to 25%. A significant increase in proliferation occurred in field strengths of 0.1, 1, and 20 mV/cm when the signal was applied continuously for six hours. Significant proliferation also occurred when the 20-mV/cm field was pulsed for six hours at 5 milliseconds ON/495 milliseconds OFF and at 5 milliseconds ON/245 milliseconds OFF. No change in alkaline phosphatase activity occurred in the 20-mV/cm field with any signal. At 1 mV/cm, there was a significant decrease in alkaline phosphatase activity in the continuous signal and in the 5 milliseconds ON/62 milliseconds OFF signal; in the lower fields evaluated, there was an actual decrease in alkaline phosphatase activity with some of the signals. The field strength plays a dominant role in determining the bone-cell's proliferative response, and to a lesser extent the alkaline phosphatase activity response, to a capacitively coupled electric field. The pulse configuration and the duty cycle are also important, but only if the proper field strength is being applied to the cell.     

Drug-resistant tuberculosis in an urban population including patients at risk for human immunodeficiency virus infection.

In the past 5 yr, an increased incidence of tuberculosis has been noted in the United States. Simultaneously, the population infected with human immunodeficiency virus-type I (HIV-I) and the number of cases of acquired immunodeficiency syndrome (AIDS) have increased. Selected areas of the United States have also reported increases in the frequency of drug-resistant isolates of Mycobacterium tuberculosis. Because our institution serves a population in which tuberculosis, AIDS, and drug resistant isolates of M. tuberculosis are frequently encountered, we sought to better define interrelationships among these factors by retrospectively reviewing the demographic, clinical, bacteriologic, and radiologic data for all adult patients in whom M. tuberculosis was isolated from a culture of respiratory-tract secretions during a 1-year period (June 1, 1988 to May 31, 1989). Two hundred forty-six patients were thus identified; 66.5% were U.S. born blacks, and 62.6% were 17 to 40 yr of age. Risk factors for HIV infection were present in 106 patients. The overall resistance rate (one or more drugs) = 30.9%, with primary resistance = 22.6% (35 of 155) and secondary resistance = 49.2% (29 of 59). In addition, 12 resistant isolates were found in 32 patients whose prior treatment status was indeterminate. Of the resistant isolates, 56.6% (43 of 76) were multiply resistant. Isoniazid resistance was noted in 90.7% (69 of 76) and rifampin resistance was noted in 50% (38 of 76) of the resistant isolates. No significant differences in the overall frequency of resistance were noted in patients at risk for HIV infection compared with those without these risks.(ABSTRACT TRUNCATED AT 250 WORDS)     

Laser treatment of eye disorders in children.

The increasing range of indications for laser treatment and the development of new modalities of lasering have led to a growing tendency to extend this type of treatment to the pediatric population. Problems of compliance in this age group often necessitate the use of general anesthesia. This report describes the operative technique used in 11 children (13 eyes) under the age of 13 years, all of whom underwent laser treatment under general anesthesia for a variety of ocular conditions. Argon or krypton laser photocoagulation was performed in eight children (10 eyes), seven of whom were treated for various retinal pathologies and one for an iris cyst. The other three children underwent Nd:YAG posterior capsulotomy for secondary cataract.     

C1 esterase inhibitor deficiency in X-linked hypogammaglobulinaemia: an anomaly fostering anaphylactoid reactions following intramuscular gammaglobulin administration

A patient with apparent X-linked agammaglobulinaemia was found to be inordinately susceptible to anaphylactoid reactions to intramuscular injections of gammaglobulin. The patient was found also to have low levels of C1 esterase inhibitor (C1 INH). The possibility that the C1 INH deficiency and in this patient, whether genetic or acquired, fostered the susceptibility to the production of anaphylactoid reactions after gammaglobulin injections urges further studies of the association of C1 INH deficiency and anaphylactoid reactions to gammaglobulin injections. The possibility that C1 INH levels like C1q levels may be low in hypogammaglobulinaemic patients as a consequence of increased catabolism of this regulator of the complement system when IgG levels are low is considered.