Expert: Dr. Louis N. Gotthelf - 11/20/2010

Question
Hi, I have a five year-old male pug. He's had two mast cell tumors removed in the past year, but otherwise, has had a pretty unremarkable health history.

Recently, I noticed that the skin under his arms, on his lower abdomen/torso, and around his anus have started to turn black. He seems to have lost some hair under his arms, and he does seem to be scratching a bit more than normal.

I've googled the symptoms and saw some possible causes--from hypothyroidism to bacterial/fungal infections. If it were either of the above, would other symptoms be present? Or could this be related to his mast cell issues?

Any help you can provide would be greatly appreciated!

Best, beth duncan  

Answer
Sometimes this black pigmentation is actually thickening skin.  This can be the result of allergies where there is a bacterial or fungal infection.  It is easy to treat these.  It is also easy to test for low thyroid and if that is the cause, treatment is easy.

With skin diseases there are also degrees of symptoms.  Sometimes there is no apparent itching, but severe skin disease is present.