William I. Fishbein

Urinary Delta-Aminolevulinic Acid (ALA) Levels in Lead Poisoning: II. Correlation of ALA Values With Clinical Findings in 250 Children With Suspected Lead Ingestion

The method for the determination of urinary delta-aminolevulinic acid (ALA) from random urine samples has been modified utilizing a dual disposable chromatographic column unit prefilled with resin that can be conveniently held in a support rack over a drain tray. The present procedure now permits one individual to perform as many as 1,000 analyses of urinary ALA in a normal working week. A single-blind evaluation was made of the laboratory findings and clinical impression of increased lead exposure versus the urinary ALA levels obtained in each of 250 children suspected of lead ingestion. St was found that the incidence of a correct correlation between urinary ALA and the clinical diagnosis of increased lead exposure was 91%. None of the other laboratory tests studied had a comparable degree of accuracy for the detection of early lead exposure.

Incidence of Subclinical Poliomyelitis in an Urban Area According to Age Groups

W ICKMAN recognized minor illnesses among the contacts of paralytic poliomyelitis cases.1 His postulation that these were mild forms of the disease, necessary to explain its epidemiologic behavior, was echoed in 1913 by Frost. Frost intimated that the paralytic case may perhaps be considered as a complication or accident in the course of poliomyelitis; that the disease occurs throughout the world in an endemic form, particularly in large cities; that the population of the cities becomes immunized by subclinical infection early in life, usually before 5 years of age (since older children and adults are less frequently attacked); that the disease has the seasonal distribution of enteric and insect-borne diseases, but that it is transmitted largely by person-to-person contact.2 Stocks estimated upward of 100 subclinical cases to each paralytic case in endemic areas.3 Evidence to support the above premises has gradually accumulated. Anderson and Frost reported that 1 of 5 normal adults and none of 3 normal children (ages 10, 11, and 16 years) had