Monday, April 6, 2009


This week is non-bacterial, non-viral infection week!

A 25 year old incarcerated man presents to the prison nurse complaining of severe itch, worst at night. He notes a new rash, shown above, involving the sides and webs of the fingers, the flexor aspects of the wrist, the extensor aspects of the elbows and knees, the axillary folds, the periumbilical area, the groin, the butt and thighs, and the lateral and posterior aspects of the feet. The back and head are spared. Many of these areas show excoriation and blood-tipped crusts.

Challenge: What's your diagnosis?

Image is in the public domain.


Alex said...


Craig Chen said...

hmmm good guess? :P

This is scabies caused by the mite Sarcoptes scabiei. This occurs in crowded conditions and institutionalized settings. Transmission is by direct contact, especially between parents and children. The itch is due to a delayed Type IV hypersensitivity reaction, 3-4 weeks after primary infestation. The lesion is a small, erythematous, nondescript papule. The pathognomonic burrow (shown here) is a thin, grayish, reddish, or brownish line 2-15mm long. Treatment is topical permethrin or oral ivermectin.

Sources: UpToDate; Wikipedia.