Absence of myoglobinuria in acute psychotic patients with marked elevationin serum creatine phosphokinase level

Elevated levels of serum creatine phosphokinase, muscular type (CKMM) are c aused primarily by diseased muscle fiber, Acute psychoses are often associa ted with a marked increase in serum CKMM levels, though the reason remains obscure. Since striated muscle damage is also associated with pigmenturia a nd myoglobinuria, we sought to determine whether the markedly high serum CK level of acute psychosis reflects skeletal muscle damage by evaluating uri nary myoglobin in affected patients. Baseline serum CK was measured on admi ssion in 713 consecutive acute psychotic inpatients (BPRS greater than or e qual to 40). Those showing a serum CK levels above 1000 IU/I on the first 2 days of hospitalization underwent urine collection for myoglobin testing. Patients with physical trauma or medical conditions known to cause CKemia w ere excluded. Twenty-five patients were eligible for the study. In no case did myoglobinuria or pigmenturia accompany the marked CKemia. There is an u nexpected dissociation between the robust increase in the serum CK,, levels and the absence of myoglobinuria in acute psychosis. Our negative finding may indicate that the serum CK threshold for myoglobinuria is very high (ab ove 10 000 IU/I). Alternatively, psycho;is-associated CKemia may be related to an unknown, nontraumatic, pathophysiological mechanism(s). (C) 2001 Els evier Science B.V. All rights reserved.