Lipid storage myopathy with clinical markers of Marfan syndrome: A rare association

General anesthesia with cisatracurium and sevoflurane for a patient with primary carnitine deficiency receiving L-carnitine therapy: A case report

RATIONALE

Lipid storage myopathies (LSMs) are a series of genetic disorders of lipid metabolism predominantly affecting muscle. The low incidence and lethal properties of this disease make anesthesia experience limited in such patients. Among all etiologies of LSMs, primary carnitine deficiency (PCD) is now considered highly treatable by early administration of L-carnitine, though it remains unclear whether L-carnitine is effective enough to protect diseased muscle against conventionally used neuromuscular blocking agents (NMBAs) during general anesthesia. Currently, no data are available concerning possible prolonged muscle weakness in these cases.

PATIENT CONCERNS

This case presents a 43-year-old female who was diagnosed with a PCD-induced LSM 3 years ago due to fatigability and exertional myalgias and has been treated with L-carnitine ever since. At the time of this report, she was admitted for uterine fibroids and scheduled for selective open gynecologic surgery under general anesthesia.

DIAGNOSIS

The patient's diagnosis of PCD-induced LSM was based on the clinical features, muscle biopsy, and diminished organic cation/carnitine transporter 2 (OCTN2) transporter activity in the patient's skin fibroblasts.

INTERVENTIONS

L-carnitine was taken by the patient until the morning of surgery. General anesthesia with cisatracurium and sevoflurane was selected as the anesthetic plan during the operation. The train-of-four (TOF) test was adopted as additional monitoring, particularly to track the recovery of neuromuscular function.

OUTCOMES

The patient was extubated successfully following a spontaneously restored TOF ratio (TOFR) of 0.9. Nonetheless, we recorded a prolonged efficacy of cisatracurium in the clinical duration and the recovery time with TOFRs of 0.7 and 0.9, respectively.

LESSONS

The conventional dose of cisatracurium combined with a low dose of sevoflurane can be safely used in patients with LSMs without additional anesthetic risks. Meanwhile, continuous TOF monitoring is recommended to perform high-quality anesthesia.

Friend or Foe: Lipid Droplets as Organelles for Protein and Lipid Storage in Cellular Stress Response, Aging and Disease

Lipid droplets (LDs) were considered as a mere lipid storage organelle for a long time. Recent evidence suggests that LDs are in fact distinct and dynamic organelles with a specialized proteome and functions in many cellular roles. As such, LDs contribute to cellular signaling, protein and lipid homeostasis, metabolic diseases and inflammation. In line with the multitude of functions, LDs interact with many cellular organelles including mitochondria, peroxisomes, lysosomes, the endoplasmic reticulum and the nucleus. LDs are highly mobile and dynamic organelles and impaired motility disrupts the interaction with other organelles. The reduction of interorganelle contacts results in a multitude of pathophysiologies and frequently in neurodegenerative diseases. Contacts not only supply lipids for β-oxidation in mitochondria and peroxisomes, but also may include the transfer of toxic lipids as well as misfolded and harmful proteins to LDs. Furthermore, LDs assist in the removal of protein aggregates when severe proteotoxic stress overwhelms the proteasomal system. During imbalance of cellular lipid homeostasis, LDs also support cellular detoxification. Fine-tuning of LD function is of crucial importance and many diseases are associated with dysfunctional LDs. We summarize the current understanding of LDs and their interactions with organelles, providing a storage site for harmful proteins and lipids during cellular stress, aging inflammation and various disease states.