To help determine the specificity of "loose anagen" (LA) hairs in Loose Anagen Syndrome, the presence or absence of LA hairs on a gentle but firm hair pull was evaluated in 110 normal subjects from a 0.5 to 83 y old. In children < or =10 y old, 61% had LA hairs on hair pull evaluation and 73% of all hairs obtained were LA hairs. In contrast, LA hairs were found in only two of 87 (2%) normal postpubescent subjects. The number of LA hairs was small in normal children (1-2 per hair pull) and a maximum of one out of every 6-7 hair pulls in adults, far less than that reported with Loose Anagen Syndrome. Although the mere presence of LA hairs on a hair pull test is thus not specific for LAS in children, the number per hair pull may have diagnostic significance. Correlation of these findings with the various hair disorder phenotypes currently termed Loose Anagen Syndrome will be important.

Accurate histopathologic distinction between trichoepithelioma (TE) and basal cell carcinoma (BCC) may be challenging. From 97 cases diagnosed as TE during the period 1979-1997, 73 available cases were studied with regard to: 1) stroma; 2) retraction effect; 3) papillary-mesenchymal bodies (PMB); 4) amyloid; 5) mitotic figures; 6) apoptotic cells; 7) inflammation; 8) granuloma; and 9) calcification. A judgment was made regarding diagnosis. The patients' medical records were subsequently reviewed for clinical features and possible recurrence. The diagnosis of TE was confirmed histologically in 48 (65%) of 73 cases. Fifteen cases (21%) were reclassified as BCC (RC-BCC), eight other cases (11%) were reclassified as other lesions, and two additional cases (3%) could not be confidently classified as either TE or BCC. The most helpful differentiating features were the presence of retraction effect (in 100% of RC-BCC vs. 37% of TE), myxoid stroma (in 80% of RC-BCC vs. 12% of TE) and PMB (in 20% of RC-BCC vs. 81% of TE). Unexpected findings in TE were detection of amyloid in 33%, apoptotic cells in 100%, and mitotic figures in 46%. Five of the 15 RC-BCC have recurred (33%), whereas there have been no recurrences in the confirmed TE group. A constellation of histopathologic criteria may help to discriminate problematic examples of trichoepithelioma from basal cell carcinoma.

Two infants, one with a T-cell-signaling defect resulting in a primary immunodeficiency syndrome and the other with severe combined immunodeficiency (SCID), are described. Both infants developed cutaneous infections secondary to their bacillus Calmette-Guérin (BCG) vaccinations. Both patients were from countries where BCG is routinely administered in infancy. The infant with the T-cell-signaling defect developed a disseminated infection involving the skin, while the infant with SCID developed a localized cutaneous infection at the site of his BCG immunization. These two cases resemble other reported cases of cutaneous BCG infection following routine vaccination in immunocompromised patients. Mycobacterium bovis infection should be considered in patients with cutaneous eruptions who have received BCG vaccination, especially those who are immunocompromised.

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