Syphilis: Always on the List for Patchy and Diffuse Non-Scarring Hair Loss

Non-Scarring Hair Loss May be the Only Clue to a Diagnosis of Syphilis

When it comes to the skin, there are three diseases that have long been called the ‘great imitators’. These are syphilis, leprosy and sarcoidosis. Clinically, the lesions of scalp sarcoidosis often have an orange color and may look very similar to lichen planopilaris, discoid lupus, scleroderma or even alopecia areata at first glance. Leprosy, an infection due to the bacteria Mycobacteria leprae, can sometimes mimic alopecia areata of the scalp or the eyebrows and can sometimes mimic telogen effluvium. Syphilis, due to infection with the bacterium Treponema pallidum, can also mimic alopecia areata.

Authors of a new report share an interesting case of a 20 year old with diffuse hair loss due to syphilis.

Katayama S et al., 2022

The authors described a previously healthy 20-year-old female who presented for medical attention following a 1-month history of hair loss. She had been treated with topical steroids but with little effect. Clinical examination found diffuse non-scarring non inflammatory type hair loss affecting the frontal, parietal, and temporal regions. Trichosocpy showeda small number of yellow dots and vellus hairs. Exclamation mark hairs were not observed.

The patient was otherwise healthy. There were no other skin, mucosal, or nail symptoms. She had no superficial lymphadenopathy. Laboratory investigations revealed an elevated titer of rapid plasma reagin (1:64), positive Treponema pallidum hemagglutination assay test, and a reactive fluorescent treponemal antibody absorption test. The results of serologic tests for HIV were unremarkable.

FINAL DIANGNOSIS: SYPHILITIC ALOPECIA

Based on these test results, the authors diagnosed syphilitic alopecia. Treatment with oral amoxicillin at 1500 mg/d was initiated; the RPR titer had decreased to 1:16 at 8 weeks later, and her hair growth had returned to normal at 12 weeks later

Conclusion

This is a helpful case that reminds us that we always need to keep syphilis on the list of conditions that mimic telogen effluvium as well as alopecia areata. About 4 to 12 % of those with secondary syphilis will develop alopecia and this happens about 3-5 months after the primary syphilis infections.

Most patients who have alopecia with secondary syphilis will also show other signs such as a classic scaly rash on the palmar surface of the hands or plantar side of the feet or show a body maculopapular rash and have mucous patches. In this particular report, the only sign that was present was the hair loss.

Syphilis is important for all clinicians to be aware of because rates of infection are increasing in many counties around the world.

REFERENCE

Katayama S et al. Rapidly Progressive Hair Loss May Be the Only Sign of Syphilis. Am J Med 2022 Feb 22;S0002-9343(22)00130-9.