A 35-year-old man with uncomplicated well-controlled HIV on bictegravir, emtricitabine, and tenofovir alafenamide presented to the emergency department with multiple facial lesions for 7 days. The first lesion was a small pustular "bump" on his lip. He subsequently developed 4 more lesions on his lips and chin before seeking an evaluation by a physician. Lesions were flesh-colored with a central concavity and small pustular discharge (Image 1). They were non-pruritic and non-tender. Concurrent with the onset of these lesions, he also developed mild right-sided submandibular pain associated with lymphadenopathy.
The patient identifies as bisexual with a history of oral and anal intercourse. The last sexual contact was 2 months prior. He then traveled to Hawaii 3 weeks prior to the index presentation and attended a large public gathering.
Lesions were swabbed for mpox virus using viral culture media and sent to a contracted commercial reference lab for qualitative PCR testing. He returned home to self-isolate. Results were available after 4 days. The reference lab notified the local public health department per Laboratory Response Network protocol. Public health officials informed the patient's infectious disease physician who arranged a clinic visit following infection control precautions as recommended by the CDC.
At the clinic visit, his original facial lesions had increased in size and central crusting (Image 2). He had also developed a new diffuse maculopapular rash on the neck, chest, and torso with a herald patch on the right chest (Image 3). Early eczema versus secondary syphilis was the concern at this time. His lymphocyte CD4 count was 588 per cubic millimeter (reference range, 500-1500), and his HIV viral load was undetectable.
After the patient was provided informed consent for use of tecovirimat for treatment of non-variola orthopox virus infection under CDC Expanded Access Investigational New Drug Protocol No. 116 039 (IRB No. 6402), he was started on tecovirimat 600 mg twice a day for 14 days. A small supply had already been arranged by the pharmacy department in coordination with the CDC, California Department of Public Health, and Kern County Public Health Department a few weeks in advance for possible local outbreaks.
Co-infection testing eventually revealed reactive syphilis antibody, reactive Fluorescent Treponemal Antibody Absorption test, and reactive Rapid Plasma Reagin test (RPR) with titer 1:1. Through California Reportable Disease Information Exchange, no prior treatment history for syphilis was found. Syphilis was staged as secondary syphilis. He was treated with 2.4 million units of benzathine penicillin G intramuscularly once. Urine gonorrhea and chlamydia nucleic acid amplification testing was negative.
At follow-up 1 week (Images 4 and 5) and 3 weeks (Images 6 and 7) after treatment initiation, he showed improvement and subsequent resolution of all symptoms. Isolation was lifted after all lesions had resolved, 4 weeks after symptom onset.