title: Acquired perforating calcific collagenosis after topical calcium chloride exposure.
abstract: A 24-year-old healthy man presented with a 6-week history of numerous umbilicated coalescing erythematous papules with some scale and crust on his anterior medial thighs. The eruption began 1 to 2 weeks after he spilled calcium chloride rock salts on his pants while salting the sidewalk during a snow storm. The salts dissolved and remained in contact with his skin for at least 4 hours until he was able to change clothes. A skin biopsy shows thick and thin collagen fibers with partial calcification in the papillary and upper reticular dermis associated with a sparse infiltrate of neutrophils, lymphocytes and mononuclear histiocytes. There are foci of transepidermal elimination of calcified fibers with adjacent epidermal hyperplasia and ortho- and parakeratosis. Von Kossa stain highlights calcification of the fibers, and trichrome stain confirms the fibers are collagen. A Verhoeff-van Gieson stain shows no abnormality of elastic fibers. The patient was treated with topical betametasone diproprionate cream twice daily for 3 weeks, as well as a short course of oral levofloxacin and topical gentamicin cream. The lesions resolved over 3 weeks with residual scarring. We report a unique case of acquired perforating calcific collagenosis secondary to topical calcium chloride exposure.
authors.affiliation: Department of Dermatology, New York University, Langone Medical Center, New York, NY 10016, USA. rishi.patel@nyumc.org
authors.forename: Rishi R
authors.initials: RR
authors.lastname: Patel
authors.forename: Monib
authors.initials: M
authors.lastname: Zirvi
authors.forename: Ruth F
authors.initials: RF
authors.lastname: Walters
authors.forename: Hideko
authors.initials: H
authors.lastname: Kamino
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001623:Betamethasone / Q000627:therapeutic use; D002114:Calcinosis / Q000139:chemically induced* / Q000188:drug therapy / Q000473:pathology; D002122:Calcium Chloride / Q000633:toxicity*; D002921:Cicatrix / Q000473:pathology; D003095:Collagen Diseases / Q000139:chemically induced* / Q000473:pathology; D004359:Drug Therapy, Combination; D004547:Elastic Tissue / Q000473:pathology; D006801:Humans; D064704:Levofloxacin; D008297:Male; D020556:Neutrophil Infiltration; D015242:Ofloxacin / Q000627:therapeutic use; D012867:Skin / Q000473:pathology*; D012871:Skin Diseases / Q000139:chemically induced* / Q000188:drug therapy / Q000473:pathology; D013848:Thigh; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D000893:Anti-Inflammatory Agents; D064704:Levofloxacin; D001623:Betamethasone; D015242:Ofloxacin; D002122:Calcium Chloride