AbstractThe case is reported of a 13 year old diabetic girl with recurrent “cold abscess” at the site of insulin injections in the thighs, from which Mycobacterium chelonei was grown. The possibility of contamination of injection sites from the skin is discussed, but the evidence is inconclusive.Although it is uncommon, the possibility of infection by atypical Mycobacterium should be kept in mind in patients who have repeated abscesses or suppurating glands, from which cultures for pyogenic organisms are sterile. The difficulty of growing such a fastidious micro‐organism is stressed, so that in many cases direct confirmation of the infection by culture is impossible, in which case indirect evidence from a PPDObranoble from Mycobacrerid Reference Loborarory, Cardiff.skin test may be he