Sertraline-Associated Rhabdomyolysis

MADD-like pattern of acylcarnitines associated with sertraline use

Multiple acyl-CoA dehydrogenase deficiency (MADD) is a primary mitochondrial dysfunction affecting mitochondrial fatty acid and protein metabolism, caused by biallelic pathogenic variants in ETFA, ETFB, or ETFDH genes. The heterogeneous phenotypes associated with MADD have been classified into three groups: neonatal onset with congenital anomalies (type 1), neonatal onset without congenital anomalies (type 2), and attenuated and/or later onset (type 3). Here, we present two cases with biochemical profiles mimicking late-onset MADD but negative genetic testing, associated with the use of sertraline, a commonly used antidepressant. Case 1 is a 22 yo woman diagnosed with depression and profound fatigue who was referred to the metabolic clinic because of carnitine deficiency and a plasma acylcarnitine profile with a MADD-like pattern. Case 2 is a 61 yo woman with a history of chronic fatigue who was admitted to the emergency department with difficulty swallowing, metabolic acidosis, and mild rhabdomyolysis. Plasma acylcarnitine profile showed a MADD-like pattern. The muscle biopsy revealed lipid droplet accumulation and proliferation of mitochondria with abnormal osmiophilic inclusions, and a biochemical assay of the respiratory chain showed a deficit in complex II activity. In both cases, urine organic acid profile was normal, and genetic tests did not detect variants in the genes involved in MADD. Sertraline was on their list of medications and considering its association with inhibition of mitochondrial function and rhabdomyolysis, the team recommended the discontinuation under medical supervision. In Case 1 after discontinuation, the plasma acylcarnitine test normalized, only to return abnormal when the patient resumed sertraline. In Case 2, after sertraline was discontinued rhabdomyolysis resolved, and the muscle biopsy and biochemical assay of the respiratory chain normalized. Although sertraline is considered a safe drug, these two cases suggest that the use of sertraline may be associated with a potentially reversible form of mitochondrial dysfunction mimicking MADD. Further studies are needed to confirm and estimate the risk of MADD-like presentations with the use of sertraline, as well as identifying additional contributing factors, including genetic factors. Metabolic physicians should consider sertraline use in the differential diagnosis of MADD, particularly when genetic testing is negative.

Lipid storage myopathy associated with sertraline treatment is an acquired mitochondrial disorder with respiratory chain deficiency

Lipid storage myopathies are considered inborn errors of metabolism affecting the fatty acid metabolism and leading to accumulation of lipid droplets in the cytoplasm of muscle fibers. Specific diagnosis is based on investigation of organic aids in urine, acylcarnitines in blood and genetic testing. An acquired lipid storage myopathy in patients treated with the antidepressant drug sertraline, a serotonin reuptake inhibitor, has recently emerged as a new tentative differential diagnosis. We analyzed the muscle biopsy tissue in a group of 11 adult patients with muscle weakness and lipid storage myopathy which developed at a time when they were on sertraline treatment. This group comprise most patients with lipid storage myopathies in western Sweden during the recent nine-year period. By enzyme histochemistry, electron microscopy, quantitative proteomics, immunofluorescence of the respiratory chain subunits, western blot and genetic analyses we demonstrate that muscle tissue in this group of patients exhibit a characteristic morphological and proteomic profile. The patients also showed an acylcarnitine profile in blood suggestive of multiple acyl-coenzyme A dehydrogenase deficiency, but no genetic explanation was found by whole genome or exome sequencing. By proteomic analysis the muscle tissue revealed a profound loss of Complex I subunits from the respiratory chain and to some extent also deficiency of Complex II and IV. Most other components of the respiratory chain as well as the fatty acid oxidation and citric acid cycle were upregulated in accordance with the massive mitochondrial proliferation. The respiratory chain deficiency was verified by immunofluorescence analysis, western blot analysis and enzyme histochemistry. The typical ultrastructural changes of the mitochondria included pleomorphism, dark matrix and frequent round osmiophilic inclusions. Our results show that lipid storage myopathy associated with sertraline treatment is a mitochondrial disorder with respiratory chain deficiency and is an important differential diagnosis with characteristic features.