The role of creatine kinase in the diagnosis of Neuroleptic Malignant Syndrome

Abstract

SynopsisElevation of serum creatine kinase (CK) concentrations occurs almost invariably in neuroleptic malignant syndrome (NMS). However, the role of CK levels in the diagnosis of the syndrome remains controversial. This study measured CK levels in patients who became pyrexial while on psychotropic medication and thereby mimicked some of the features of NMS. In all of these cases a diagnosis of infectious illness was made and patients responded to appropriate antibiotic therapy without alteration in psychotropic medication. Two other groups were studied for comparison – patients on psychotropics who were apyrexial and patients who became pyrexial but were not on psychotropics. Significant, unexpected elevations of CK were documented in 70% of those patients who became pyrexial while on psychotropics – in three cases elevation of concentrations to more than 1000 IU/1 (ten times reference value) were found. Thirty per cent of patients who became pyrexial but were not on psychotropics also developed elevation of CK but this was of a much smaller magnitude (lt; 200 IU/1 in five out of six cases). The results of the study suggest that elevation of CK is a non-specific finding, particularly in patients who become pyrexial on psychotropics. Use of CK as a diagnostic criterion may lead to overdiagnosis of NMS.

Potential Interaction between Celecoxib and Warfarin

“…Celecoxib undergoes hepatic metabolism by CYP2C9, which also is the isoform through which the S-enantiomer of warfarin is m e t a b o l i z e d . 3 Although celecoxib did not appear to alter the pharm acokinetics of R-or S-warfarin in volunteers, it may cause an interaction in elderly patients. 3 Various factors must be considered when designing pharmacotherapeutic regimens for geriatric patients, since they often consume multiple drugs, suffer from multiple diseases, and exhibit agerelated changes in pharmacokinetics such as decrements in renal and hepatic function.…”

“…3 Although celecoxib did not appear to alter the pharm acokinetics of R-or S-warfarin in volunteers, it may cause an interaction in elderly patients. 3 Various factors must be considered when designing pharmacotherapeutic regimens for geriatric patients, since they often consume multiple drugs, suffer from multiple diseases, and exhibit agerelated changes in pharmacokinetics such as decrements in renal and hepatic function. 4 Indeed, an age-related decrease in the content and function of CYP2C9/10 has been documented.…”

Neuroleptic Malignant Syndrome: Three Adolescents with Complicated Courses

“…Both symptoms must develop within 2 weeks of neuroleptic exposure. Elevated CPK is included in the diagnostic criteria by most (Latz andMcCracken 1992, Levenson 1985) but not all (Adityanjee 1991, O'Dwyer and Sheppard 1993, Shalev et al 1989 authors. Other suggested criterion symptoms include disturbed consciousness, autonomie instability, diaphoresis, sialorrhea, dysarthria, dysphagia, tremor, and incontinence (Buckley et al 1991, Deuschl et al 1987.…”

Elevated creatine kinase does not necessarily correspond temporally with onset of muscle rigidity in neuroleptic malignant syndrome: a report of two cases

“…Serum CK elevation is not specific to NMS,5 but is reported to be found in over 90% of patients with NMS 3,6. Therefore, an elevated CK level is suggestive of NMS.…”