Tuberculous perihepatic abscess and neurosarcoidosis: report of 2 uncommon manifestations of 2 common granulomatous diseases in 1 patient.

Infections caused by pathogens of the Mycobacterium tuberculosis complex, i. e., tuberculosis (TB), and the non-infectious, autoimmune disease sarcoidosis are among the most common granulomatous diseases worldwide. Typically, the lung is the primary site of infection and manifestation, respectively which makes the two diseases important differential diagnoses. Both diseases can affect virtually all organ systems, albeit with significantly lower incidence. CASE PRESENTATION:  We report the case of a 50-year-old Indian man presenting with a tuberculous perihepatic abscess and a systemic inflammatory response after being diagnosed with neurosarcoidosis presenting as a single granuloma in the frontal lobe with lymphadenopathy in 2014. On day of admission the patient presented with right upper abdominal pain and fever for two weeks. With increased inflammatory parameters in serum and after finding of external CT images, a perihepatic abscess was suspected. This encapsulated cave was drained percutaneously under CT control. A high concentration of acid-fast rods was detected using ZN, PCR was positive for M. tuberculosis. Several samples of sputum and urine were microscopically negative but yielded growth of Mycobacteria after four weeks. DISCUSSION:  This is a case presenting with two different granulomatous diseases, each of which manifested itself in an atypical form. The tuberculous liver abscess might either be explained as a flare-up of latent tuberculosis under azathioprine therapy or as a reinfection acquired during one of several visits in the high-prevalence country India. In addition, it must be discussed whether the cerebral granuloma in 2014 could have been an early stage of tuberculous granuloma. Sensitivity of ZN staining is significantly reduced in cerebral samples, and negative PCR-results might be due to low germ load or methodical issues, e. g., decreased sensitivity in formalin fixated samples.