The purpose of this study was to report severe keloids caused by hydrogen cyanide injury. Hydrogen cyanide poisoning is still a problem as an occupational disease in China. We report a 37-year-old man with severe hydrogen cyanide poisoning. The patient fell on the floor after inhalation of hydrogen cyanide and was burned on his back by hydrocyanic acid. Sequential treatment included amyl nitrite by inhalation, intravenous sodium nitrite 3%, and intravenous sodium thiosulfate 25%. Other treatment consisted of incision of the trachea, mannitol and furosemide, antibiotics, and nutrient support measures. The patient also received hyperbaric oxygen therapy; during the first treatment, he became apneic and cardiopulmonary resuscitation was supplied in the hyperbaric oxygen chamber. He eventually recovered, but a large amount of keloids developed on his back and buttocks.

Jian, Guo, Ruan, Lin, Zhao, , , , (2008). Severe keloids caused by hydrogen cyanide injury: a case report. Cutaneous and ocular toxicology, 2008 ;27(2):97-101. https://www.ncbi.nlm.nih.gov/pubmed/18568895