25 y/o female presents with low grade fever, vomiting, rigors and headache 1/2 hour after injecting heroin. Vitals notable for temp of 100.5. Physical unremarkable. WBC 12, other labs normal. After IV hydration and antiemetics patient feels much better 2 hours later. What is her likely diagnosis?

Cotton fever. As part of the processing of heroin prior to injection many drug users strain the drug through cotton to rid it of impurities. This process, however, can sometimes introduce other impurities into the drug such as Enterobacter agglomerans or other nonspecific pyrogenic components which produce the symptoms described in the vignette. Treatment is supportive and symptoms generally self resolve within 24 hours. While cotton fever is a benign febrile disorder, vigilance should be maintained as there are many not-so-benign causes of fever in the intravenous drug user.


Source

Ramik, D. and Mishriki, Y. "The Other 'Cotton Fever'" Infectious Disease in Clinical Practice. May 2008.

Marx: Rosen's Emergency Medicine, 7th ed.

Shannon: Haddad and Winchester's Clinical Management of Poisoning and Drug Overdose, 4th ed.