Monday, September 8, 2008

Day #67 - Malignant Ascites

Previously I have talked about cirrhosis, ascites, and paracentesis.

The take home point from today's case was that you should be suspicious of a malignant cause of ascites when there is massive ascites without leg edema. The overwhelming majority of patients with ascites from portal hypertension will have leg edema. In this case the cause was an adenocarcinoma seen on cytology.

TB peritoneal disease can mimic a cancer. In fact, sometimes tumour markers such as CA-125 are elevated in TB peritoneal disease mimicking ovarian cancer. The diagnosis of TB peritonitis can be difficult.

The cell count is usually in the hundreds with a lymphocytic predominance.

The SAAG is usually <11.

Adenosine deaminase may be elevated -- if you can measure it.

Obviously the cytology for malignancy will be negative; however, the ascitic fluid rarely stains positive for AFB and the cultures are often negative. AMTD has a higher yield, but it is still disappointing.

Diagnosis usually requires a peritoneal biopsy sent for AFB stain as well as MTB culture.

There is a great nejm case of TB peritonitis here.

A huge (and awesome) free textbook on tuberculosis is available online here.

No comments: