Progressive macular hypomelanosis is a common entity and is often mistaken for tinea versicolor and pityriasis alba; however, it is unresponsive to medications for these conditions. The authors of this interesting article had previously noted a red fluorescence of the follicles of affected skin in affected patients. Using biopsy specimens of lesional and healthy follicular skin as well as lesional and healthy interfollicular skin in 8 patients, they demonstrated gram-positive rods in the affected follicles but not in the unaffected follicles or the interfollicular skin. Culture of the affected follicles yielded Propionibacterium acnes in 7 of the 8 patients, while the unaffected follicles and the nonfollicular skin did not yield this organism. No spores or hyphae were visible in any biopsy specimens (stained with periodic acid–Schiff).