Figure 1. Hypermetabolic and enlarged abdominal lymph nodes are present (up to SUV_max 4.2).

Figure 2. Multiple hypermetabolic abdominal lymph nodes are again seen, in the peripancreatic region, small bowel mesentery and pre- and para-aortic regions (up to SUV_max 7.5).

In the liver, there is a single focus of mildly increased uptake in segment IV (SUV_max 1.2), which corresponds to a 0.4cm hypoenhancing lesion on CT (not shown). The spleen has been removed. In the lateral aspect of the left thigh, there are 2 hypermetabolic soft tissue nodules in the vastus lateralis muscle (SUV_max 2.0 and 1.2). Further small subcutaneous foci with low-grade uptake are present in both lower limbs (larger in left leg, SUV_max 0.6) and in the left shoulder (SUV_max 1.2). There is hypermetabolic activity in the tongue.

There is heterogeneous abnormal uptake in the skeleton.

Figure 3. There is an hypermetabolic lesion in the proximal left ulna that causes cortical disruption. 

Severe combined immunodeficiency (SCID) represents a number of genetically distinct syndromes with defects in humoral and cell mediated immunity. Patients with SCID are susceptible to recurrent, severe infections by a wide range of pathogens. Currently, bone marrow transplantation is the mainstay of treatment, and without this, death usually occurs within the 1st year of life.

Tuberculosis can involve any body system, with abdominal TB the 6th commonest site of extra-pulmonary involvement after lymphatic, genitourinary, bone and joint, miliary and meningeal tuberculosis. Peritoneal tuberculosis (TB) can markedly accumulate FDG. 

The skeletal lesions in this case were presumed to represent chronic multifocal osteomyelitis, though a pathogen was not isolated. The tongue uptake is accounted for by the infant's sucking action just prior to the scan.