January, 2008

Case 219:
Five hunters spent a weekend in a cabin in the Northeastern United States.  One of the hunters, who slept in a sleeping bag on the floor of the cabin, awoke in the morning with a rash on various parts of his body (Figure A).  Because the area was endemic for Lyme disease, public health officials wanted to search for the tick vector.  Arthropods (Figures B and C) found under a rug in the cabin were collected and sent to the state public health laboratory for identification.  What is your diagnosis?  Based on what criteria?

A	B

C

Acknowledgement: These images were kindly contributed by Dr. Harold Harlan and the Armed Forces Pest Management Board.

Click here for the answer to Case 219.

Case 220:
A woman found a worm in her laundry basket and contacted the health department in her state for assistance.  She reported small children in the household, as well as dogs and cats.  The worm was examined at the state health laboratory; it measured approximately 7.5 centimeters in length (Figure A).  Eggs were removed from the worm and an iodine-stained wet mount was made.  Images were sent to DPDx for diagnostic assistance.  Figure B was taken at 100× magnification.  Figure C was taken at 400× magnification and measured approximately 75 micrometers.  What is your diagnosis?  Based on what criteria?  What other feature(s) would be helpful for identification?

A	B

C

Click here for the answer to Case 220.

Acknowledgement: This case and the images were kindly contributed by the Alaska State Public Health Laboratory.

Case 219: Fifty-two out of 62 respondents correctly identified this as a case of bed bug infestation caused by Cimex sp.
Case 220: Fifty out of 61 respondents correctly identified the worm as belonging to the genus Toxocara.

Images presented in the monthly case studies are from specimens submitted for diagnosis or archiving.  On rare occasions, clinical histories given may be partly fictitious.