Rectal syphilis in a HIV patient from Peru

Area of Science:

• Infectious Diseases
• Gastroenterology
• HIV Medicine

Background:

• Ulcerative and erosive proctitis are common in individuals with Human Immunodeficiency Virus (HIV) infection.
• Differential diagnosis for proctitis in HIV-positive men who have sex with men (MSM) is broad.
• Syphilis, caused by Treponema pallidum, can present with diverse clinical manifestations.

Observation:

• A 53-year-old MSM presented with inguinal adenopathy, a penile ulcer, and symptoms of tenesmus, rectal bleeding, and pain.
• Proctoscopy revealed a deep rectal ulcer with indurated edges and surrounding mucosal erosions.
• Biopsy confirmed lymphomononuclear infiltration and granulomas, with Warthin-Starry staining identifying spirochetes.

Findings:

• The patient tested positive for HIV (CD4: 275 cells/uL, viral load: 10,300 copies/mL).
• Serological tests showed a positive FTA-Abs (1:10) and non-reactive VDRL.
• Warthin-Starry staining of the rectal ulcer biopsy definitively identified spirochetes, suggesting a likely diagnosis of secondary syphilis co-infection.

Implications:

• This case underscores the importance of considering and actively investigating for spirochetal infections, such as syphilis, in HIV-positive patients presenting with proctitis.
• Prompt identification and treatment with penicillin G led to symptom resolution, emphasizing the efficacy of appropriate antimicrobial therapy.
• The findings highlight the diagnostic value of Warthin-Starry staining in identifying spirochetes in challenging cases of ulcerative proctitis within the context of HIV infection.