Diagnosis: This patient has bed bug bites. The rash has the characteristic “bites in a row” pattern consistent with bed bug bites. The bugs were probably in the mattress of the bed the woman slept on but not her spouse’s mattress. She likely brought them home in her clothing or bedding, and is continuing to get bitten by them at night while she sleeps. Her clothing may not have been cleaned adequately or she may have missed some exposed garments or bedding.
Bed bugs typically feed at night on exposed areas of skin, usually arms, legs, face, and neck, whereas scabies burrow under the skin, making curvy lines on the hands, feet, and beltline. Bed bug bites are similar to other insect bites, in that they are typically small, urticarial wheels with a central blood dot. The line of bites is thought to be from a single bug probing the skin for superficial capillaries, or multiple bugs lining up at the edge of clothing or bedding. The bite and itching typically occur upon awakening, but some patients may not experience itching for up to 10 days. Some patients do not react at all to the bites. In industrialized countries, treatment of the home for bed bugs should be done be exterminators skilled in their removal and generally involves chemicals and heat to kill all the remaining bugs. Clothing and personal items should be washed and dried at a high temperature (122°F). Mattresses should be sealed in plastic or replaced.
Acknowledgement: Case presented by Tracey Quail Davidoff, MD, an urgent care physician at Accelcare Medical Urgent Care in Rochester, NY.