Beryl J. Rosenstein

A double-blind controlled trial of anti-Pseudomonas chemotherapy of acute respiratory exacerbations in patients with cystic fibrosis

A double-blind controlled trail of anti-Pseudomonas chemotherapy was carried out in 24 exacerbations of pulmonary disease in patients with cystic fibrosis. Fifteen exacerbations were treated with oxacillin plus sisomicin and carbenicillin (treatment group); nine were treated with oxacillin alone (control group). The planned length of treatment was 14 days. The difference between the failure rate in the treatment group (3/15) and the control group (7/9) was statistically significant (P less than 0.015). The difference in improvement of forced expiratory volume in 1 second was also significant (P less than 0.025). At the end of the study, Pseudomonas aeruginosa was still present in the sputum of all nine patients in the control group, but was not isolated from six of the 15 patients in the treatment group. The data suggest a beneficial role for anti-Pseudomonas chemotherapy in the treatment of acute pulmonary exacerbations in patients with cystic fibrosis.

Congenital Renal Abnormalities in Infants with in Utero Cocaine Exposure

To determine the incidence of renal abnormalities among infants exposed to cocaine in utero, we performed ultrasound studies of the genitourinary tract in 100 consecutive infants admitted to the full-term nursery whose mothers had a history of cocaine use during pregnancy and/or a maternal toxicology screen was positive for cocaine. Mean gestational age of the newborns was 38.4 +/- 2.1 weeks. Mean birth weight was 2,846 +/- 561 gm.; 26% of the patients were less than 2,500 gm. and 18% were small for gestational age. Symptoms of drug withdrawal were present in 47 patients. Two newborns had murmurs consistent with a ventricular septal defect. On ultrasonography, 1 newborn had a unilateral multicystic/dysplastic kidney and 1 had kidneys that were 2 standard deviations below normal in size. Based on our results routine renal ultrasound studies do not appear to be indicated in full-term newborns exposed in utero to cocaine.

Prenatal care and drug use in pregnant women

This case-control study tested the hypothesis that pregnant inner-city women with low utilization of prenatal care are likely to be frequent drug users. Cases registered consecutively for prenatal care at > or = 28 weeks gestation or had < 4 prenatal visits. Controls were matched to cases by date of delivery. 24/81 (30%) cases and 16/128 (12%) controls were frequent drug users (adjusted odds ratio = 2.5; 95% CI, 1.2-5.4). Drug use (P = 0.01) and socioeconomic status (P = 0.001) were significantly correlated with prenatal care utilization. Self-report alone failed to note as many drug users as toxicology screen alone. Both substance use history and toxicology screen are advisable in women with low utilization of prenatal care.

Misdiagnosis of Cystic Fibrosis: Need for Continuing Follow-up and Reevaluation

A retrospective review was conducted of the charts of 271 patients with a diagnosis of cystic fibrosis (CF) who were evaluated over a 15-year period at the Johns Hopkins Hospital. Among these patients, eight were encountered in which the diagnosis of CF was made on the basis of a compatible clinical picture and at least two positive quantitative pilocarpine iontophoresis sweat tests but who were subsequently documented to have normal sweat electrolyte concentrations. Six of the eight patients had recurrent episodes of cough and wheezing without evidence of suppurative pulmonary disease. Our experience suggests that variability in sweat electrolyte concentrations may occur more commonly than is generally appreciated. In those patients who do not follow a typical course, it is crucial to repeat sweat tests, even if the initial diagnosis was based on two or more positive quantitative pilocarpine iontophoresis sweat tests performed in a CF referral center.

False-positive results of genetic testing in cystic fibrosis

We describe a patient in whom newborn immunoreactive trypsin screening and mutation analysis suggested a diagnosis of cystic fibrosis; however, the clinical course and sweat test results were not consistent with the diagnosis. Direct sequencing of the patients genomic DNA showed compound heterozygosity for delta F508 and F508C, a polymorphism not associated with clinical disease.

Diagnosis of cystic fibrosis during adolescence

The manifestations of cystic fibrosis (CF) may be minimal, absent, or overlooked during childhood, thus 8-10% of cases are diagnosed during adolescence. Between 1970 and 1982, 14/157 (8.9%) patients were diagnosed as having CF as teenagers, based on clinical findings and elevated sweat electrolyte levels. Of these 14 patients (means = 15 years, range = 12-20 years), 50% had pulmonary and gastrointestinal symptoms dating from childhood; 50% became symptomatic during adolescence (primarily with pulmonary manifestations). None had a family history of CF. Four had false-negative sweat tests resulting in a mean diagnostic delay of 7.3 years. Because of the potential long-term complications of CF on physical maturation, completion of the psychosocial tasks of adolescence, adaptation to a chronic illness, and issues of sexuality and fertility, consideration of this diagnosis is crucial.

Moxalactam-tobramycin-resistant Pseudomonas aeruginosa Isolates in Patients with Cystic Fibrosis

In vitro studies have shown synergistic killing activity against Pseudomonas aeruginosa (PA) with the combination of an aminoglycoside and moxalactam, a new beta-lactam agent. We describe three patients with cystic fibrosis (CF) with PA isolates that were resistant to all single-agent antibiotics, but sensitive to the combination of moxalactam-tobramycin. Initially, all patients had a good clinical response to this combination. However, during a second course of therapy, there was clinical deterioration coincident with the rapid emergence of moxalactam-tobramycin-resistant PA isolates.