In addition to the usual routine haematologic and biochemical investigations, the serum calcium, phosphorus, magnesium, alkaline phosphatase, calcitonin and parathyroid hormone should also be measured. The cerebrospinal fluid (CSF) should be examined to exclude bacteria, viruses and parasites. The Ellsworth Howard test (a 10-20 fold increase of urinary cyclic AMP excretion following stimulation with 200 micromoles of parathyroid hormone) may be worth doing also. Serology for toxoplasmosis is also indicated.<unk>  CT scan is the preferred method of localizing and assessing the extent of cerebral calcifications. Elevated levels of copper, iron, magnesium and zinc but not calcium have been reported in the CSF but the significance of this finding — if any — is not known. The diagnosis requires the following criteria be met: # the presence of bilateral calcification of the basal ganglia # the presence of progressive neurologic dysfunction # the absence of an alternative metabolic, infectious, toxic or traumatic cause # a family history consistent with autosomal dominant inheritance The calcification is usually identified on CT scan but may be visible on plain films of the skull. Differential diagnosis Basal ganglia calcification may occur as a consequence of several other known genetic conditions and these have to be excluded before a diagnosis can be made.
Primary familial brain calcification
Generalized arterial calcification of infancy
Cerebral arteriovenous malformation
Normolipoproteinemic xanthomatosis
Osteopathia striata
Vertebral hemangioma
Intravascular lymphomas
Gerodermia osteodysplastica