Isolation and identification of nontuberculous mycobacteria from foods as possible exposure sources.

A variety of foods collected from local supermarkets and produce stands were examined as possible sources of nontuberculous mycobacterial exposure. Food samples were combined with sterile ultrapure water and manually shaken. To remove large particles, the suspensions were filtered through a sterile strainer, centrifuged, and the supernatants were discarded. The food pellets were stored at -75 degrees C. The pellets were treated with either oxalic acid or sodium hydroxide-sodium citrate solutions to reduce contamination by nonmycobacterial organisms. Decontaminated pellets were cultured on both Middlebrook 7H10C agar and Middlebrook 7H10C agar with supplemental malachite green. Plates were observed for growth at 2 and 8 weeks. Isolates demonstrating acid-fastness were identified to species using polymerase chain reaction and restriction enzyme analysis. Nontuberculous mycobacteria (NTM) were recovered from 25 of 121 foods. Six different species of NTM were isolated, the most predominant being Mycobacterium avium.

Pertussis immunization and characteristics related to first seizures in infants and children.

In a previous study in which we examined the relationship of pertussis immunization to the onset of neurologic disorders during 1967 and 1968 and during 1972 and 1973 in Denmark, there were 554 children with initial onset of epilepsy and 2158 children with first febrile convulsions. In the study population there were 112 children with epilepsy and 229 children with febrile convulsions for whom the exact date of pertussis immunization and the exact date of the onset of illness were known. We analyzed selected clinical variables by specific time intervals between pertussis immunization and the first seizure. In the children with epilepsy, no relationship was found between time of pertussis immunization and the specific variables that were examined. In contrast, the following characteristics in children with febrile seizures were significantly more common when pertussis immunization had occurred within 3 days, compared with more than 7 days of the event: first seizure more than 10 minutes in duration, the occurrence of more than one seizure, the longest seizure (when there was more than one) more than 10 minutes in duration, and the occurrence of a seizure described as focal. The lack of specific characteristics in epilepsy that had its onset in a temporal relationship to pertussis immunization is further evidence that pertussis vaccine does not cause this disorder. The cause of increased severity of febrile seizures apparently associated with pertussis immunization is unknown.

Typical, modified, and atypical measles.

A small outbreak of measles that occurred in August and September of 1975 was studied. One adolescent boy who had received killed measles vaccine 12 years previously had atypical measles, a 31-year-old woman had typical primary measles, and two other boys with measles were live vaccine failures. Of these latter two cases, clinical and serologic findings suggest that one boy had primary vaccine failure and the other may have had a secondary immunologic response. The findings of this study, as well as the results of other recent investigations, suggest that measles will be of increasing concern for the internist.