Lewis E. Gibson

Clinical evaluation of the macroduct sweat collection system and conductivity analyzer in the diagnosis of cystic fibrosis.

The purposes of this study were to compare sweat tests used in diagnosing cystic fibrosis (CF), as performed with the Macroduct collection system, with those utilizing the more laborious quantitative pilocarpine iontophoresis test (QPIT), and to ascertain the efficacy of the Sweat-Chek conductivity analyzer in eliminating some possibly unnecessary chloride analyses. A Macroduct sweat test was performed on one arm and a QPIT on the other on 1090 patients, 93 of whom had CF. Of these, 514 patients (43 with CF) also had a conductivity determination on the Macroduct sweat sample. All subjects were referred to the laboratory of one of us (K.B.H.) for sweat testing. Of the QPIT samples, 0.7% were inadequate, as were 6.1% of those from the Macroduct system. When sodium and chloride concentrations from the two tests were compared, the standard errors of the estimate were 3.90 and 3.85, respectively. Agreement within 8 mEq/L could then be expected with 95% confidence limits. With use of the Sweat-Chek analyzer, no patient with CF was found to have a conductivity of less than 90 mmol/L, whereas 430 (91%) of the non-CF subjects had a conductivity of less than 50 mmol/L. None of those 430 subjects had a sweat chloride value > 32 mmol/L. We conclude that the Macroduct collection system provides results equally as satisfactory as those provided by the QPIT and that the Sweat-Chek analyzer frequently eliminates the necessity of measuring chloride concentrations.

EVIDENCE OF ALLERGY IN PATIENTS WITH CYSTIC FIBROSIS OF THE PANCREAS

Abstract Review of the records of 135 patients with cystic fibrosis of the pancreas revealed that nineteen had evidence of atopic allergy. The diagnosis of cystic fibrosis was easily overlooked in patients with classical manifestations of atopic allergy, such as asthma, nasal polyps, hay fever, urticaria, eczema, positive skin tests, and familial allergy. Optimal therapy for many of these patients included treatment of the allergic problem as well as the usual regiment for cystic fibrosis. Forty-seven patients with atopic bronchial asthma had no evidence of the sweat chloride abnormality characteristic of cystic fibrosis of the pancreas. The nature of the relationship between cystic fibrosis of the pancreas and atopic allergy is not clear.

Home care: The next frontier of pediatric practice

An overview of pediatric home care issues reveals the breadth and scope of services available to permit pediatricians to provide care at home. This care option has undergone explosive growth and represents one of the fastest-growing health expenditures. Paradoxically, direct physician involvement in the home has been limited during this expansion because of the way home care has been designed and organized with inadequate reimbursement for physician participation, and lack of awareness by, and education of, physicians concerning their roles and responsibilities. The rationale for physician involvement in home care includes the need for determination and reevaluation of the medical necessity of home care services. Future changes in health care delivery and payment will encourage even more consideration of alternative care sites. Physician participation in program and protocol design will facilitate and encourage the appropriate use of the home as a care setting. For the pediatrician to know about home care requires the development of a curriculum to be implemented in academic centers for physicians-in-training and in professional associations for continuing medical education. This curriculum should enable physicians to become primary participants in home care and should lead to research opportunities to evaluate the benefits of home care.

Acute pancreatitis associated with congenital cyst of the common bile duct

Summary A case of congenital cystic dilatation of the common bile duct with an associated pancreatitis is presented. The literature is reviewed in an attempt to find the frequency of such an association. Five other cases were found in which both conditions coexisted. The symptoms of pancreatitis are not always sufficiently different from those of choledochus cyst to ensure the simultaneous diagnosis of both diseases when they occur together. Therefore, an awareness of the possible association may be helpful.