Duchenne muscular dystrophy and idiopathic hyperCKemia in the same family

Significance of Asymptomatic Hyper Creatine-Kinase Emia

OBJECTIVES

Whether asymptomatic hyper-CKemia (AHCE) should prompt a thorough work-up for muscle disease or not is controversially discussed. This review aims at summarizing and discussing recent findings concerning the cause, frequency, evolution, and work-up of conditions manifesting as AHCE and normal or abnormal electromyography (EMG) respectively muscle biopsy.

METHODS

Systematic PubMed search.

RESULTS

There are numerous primary (hereditary) and acquired myopathies that manifest with permanent, recurrent, or temporary AHCE with/without myopathic EMG or muscle biopsy. AHCE particularly occurs at onset of these conditions, which include dystrophinopathies, myotilinopathies, calpainopathy, caveolinopathy, dysferlinopathy, central core disease, multicore disease, desminopathy, MD1, MD2, hypoPP, malignant hyperthermia susceptibility, Pompe disease, McArdle disease, myoadenylate deaminase-deficiency, CPT2-deficiency, mitochondrial disorders, or myopathy with tubular aggregates. Most likely, other primary myopathies manifest with AHCE as well, without having been reported. Patients with AHCE should be taken seriously and repeated CK determination must be conducted. If hyper-CKemia is persisting or recurrent, these patients should undergo an EMG and eventually muscle biopsy. If noninformative, genetic work-up by a panel or whole exome sequencing should be initiated, irrespective of the family history. Patients with AHCE should avoid excessive exercise, require sufficient hydration, require counseling with regard to the risk of malignant hyperthermia, and should inform anesthesiologists and surgeons about their condition before elective surgery.

CONCLUSIONS

Recurrent AHCE should be taken seriously and managed with conventional work-up. If noninformative, genetic work-up should follow irrespective of the family history.

Approach to asymptomatic creatine kinase elevation

How to manage a patient who has an elevated serum creatine kinase (CK) level but no or insignificant muscle-related signs and symptoms is a clinical conundrum. The authors provide a systematic approach, including repeat testing after a period of rest, defining higher thresholds over which pursuing a diagnosis is worthwhile, and evaluating for a variety of nonneuromuscular causes. They also outline a workup for neuromuscular causes.