An interesting case to analyse. The abdominal radiograph demonstrates extensive areas of intrabdominal calcification. These do not conform to any intrabdominal organ, nor the bowel to suggest bowel contents. Therefore, these findings are likely peritoneal in nature.
There are not many causes of peritoneal calcification. Intuitively, tuberculosis and peritoneal mesothelioma may come to mind. However, in the former calcification is unusual and limited and localised when present. Calcification is even rarer within peritoneal mesothelioma even if pleural plaques are calcified in the same patient.
So it is important to consider other conditions. Pseudomyxoma peritonei can be associated with small areas of focal punctate or linear calcification. In these cases the bowel would be expected to be centrally displaced by the gelatinous soft tissue filling the peritoneum. This is not present in this case.
Two conditions should be considered with extensive calcifications of this type. These are psammomatous calcifications in ovarian malignancy and the calcifications of sclerosing peritonitis. These two types of calcifications can be differentiated by their morphology. Psammoma bodies are usually fluffy calcifications that appear almost to be forming ossified bodies. In distinction the calcfications of sclerosing peritonitis are usually linear or sheet like.
Therefore, in this case the calcifications are typical of sclerosing (or encapsulated) peritonitis. This is a calcification pattern that develops in patients on peritoneal dialysis. The appearances are often referred to as a "cocoon abdomen". The presence of the calcifications and peritoneal loculations impairs the ability to perform peritoneal dialysis effectively by reducing the peritoneal surface accessible to the dialysate fluid.
When identifying features of one disease it is also important to look for further features that may corroborate the process. What about the bones, are they normal? The bone density is diffusely increased, the trabeculae are ill-defined, there is alternate sclerosis and lucency of the vertebral bodies ("rugger jersey spine"). These are features of renal osteodystrophy. The sacro-iliac joints are also ill-defined and widened. This is a feature of the hyperparathyroidism component of renal osteodystrophy resulting in subperiosteal bone resorption. Finally, vascular calcifications are present. These are less specific and seen not only in renal impairment but also in diabetes and elderly patients with atherosclerosis.
The surgical clips in the pelvis are not related to a prior transplant as suggested by some, but rather due to sterilisation clips. Unrelated clips in the upper abdomen are due to unrelated surgery.
Always look at all elements of a case. The bones, the soft tissues, the gas pattern, they may all assist in confirming a diagnosis and finding all its manifestations.