Perianal Streptococcal Ecthyma



  • 34 year old MSM
  • Known HIV positive, but untreated – reluctant to take medications. CD4 65!
  • Presented with 3-4 days severe anal pain and penile rash.
  • Last prior sexual contact 3 weeks previously – hand and mutual penile contact only.



  • Also mentioned that he had a penile rash:



Day 0

  • Assessed as possible herpes, despite lack of convincing epidemiology.
  • Treated with valaciclovir and topical lignocaine.


Day 4

  • Returned, pain worse than ever.
  • No improvement clinically.
  • Perianal ulcers persisted unchanged.
  • Penile lesions slightly crusted.
  • Tests for herpesviruses, gonorrhoea, chlamydia and syphilis negative!
  • Reassessed as possible bacterial infection.
  • Gram stain showed numerous mixed bacteria.
  • Herpesvirus tests repeated.
  • Started on Amoxycillin/clavulanate pending culture results.


Day 7

  • Dramatic improvement in pain and general wellbeing.
  • Perianal ulcers greatly improved. 
  • Penile lesions developed into small healing ulcers.
  • Repeat herpesvirus tests negative.
  • Heavy growth of Group C Streptococcus on culture.
  • Amoxycillin/clavulanate continued for total of 14 days.



  • Subsequent healing uneventful
  • Eventually agreed to start antiretroviral therapy and primary PCP prophylaxis



Group C streptococcal ecthyma in HIV-immunocompromised patient



Ecthyma is a skin infection, usually caused by Streptococcus pyogenes, but also by other beta-haemolytic streptococci and Staphylococcus aureus.

It is similar to impetigo, but differs in that the infection is not superficial but invades deeper into the epidermis.  A differentiating clinical characteristic is that ulcers, rather than erythema, are seen when crusts are removed.

It is associated with immunodeficiency of varying causes, eg neutropaenia, diabetes and HIV infection.

Dated November, 2007