To the Editor:—
We would like to report our recent experience with a patient with a rare disorder known as Gitelman syndrome.
Gitelman syndrome , a variant of Bartter syndrome, is a congenital autosomal recessive disorder characterized by hypokalemia, hypomagnesemia, and hypocalcinuria associated with metabolic alkalosis.1,2Unlike Bartter syndrome, which presents in the neonatal period and childhood up to 5 yr of age, Gitelman syndrome presents in early adulthood. The two syndromes may also be distinguished from each other because Gitelman syndrome presents with hypomagnesemia and hypocalcinuria, whereas Bartter syndrome presents with normal serum magnesium and high urinary calcium.1,2Patients with Gitelman syndrome usually present with cramps, fatigue, muscle weakness, and carpopedal spasms.
A 47-yr-old woman recently presented to us for repair of nasolacrimal duct stenosis during general anesthesia. Her medical history was significant for diabetes, gastroesophageal reflux disease, and thyroid disease. Her surgical history included a hysterectomy, an appendectomy, a thyroidectomy, a breast biopsy, and an exploratory laparotomy for ovarian cancer. She described her symptoms as cramps in her legs. She related that 2 yr ago during the surgery for her thyroid, she had a cardiac arrest. The patient stated that her cardiac arrest had occurred because of unrecognized hypokalemia and hypomagnesium.
Her medications included potassium chloride, magnesium, spirolactone, levothyroxine, glyburide, and lensoprazole. Her vital signs included a blood pressure of 111/77 mmHg, pulse of 98 beats/min, respiration of 18 breaths/min, and temperature of 97.9°F. Her laboratory studies showed the following: white blood cells, 10.6 (4.1–11.2); hemoglobin, 15.3 g/dl (11.5–15.1); hematocrit, 45.0% (35–46); platelets, 503 ×103 (140–400); Na, 137 mEq/l (136–145); K, 4.2 mEq/l (3.5–5.1); Cl, 96 mEq/l (98–107); HCO2, 27 (20–27); blood urea nitrogen, 20 mg/dl (6–20); creatinine, 0.8 (0.5–1.2); glucose, 68 mg/dl (65–115); Ca, 10.9 mEq/l (8.8–10.5); Mg, 1.9 mEq/l (1.3–2.1); and urine creatinine, 181 mEq/l. She was 4 ft 11 in tall and weighed 70 kg.
In the operating room after placement of an electrocardiograph, noninvasive blood pressure cuff, and pulse oximetry, general anesthesia was induced using propofol and fentanyl with rocuronium for muscle relaxation and for tracheal intubation. Desflurane was used for maintenance of anesthesia. At the end of the case, the muscle relaxant was reversed using glycopyrrolate and neostigmine. When the patient was awake and responding to commands, her trachea was extubated in the operating room without any complications.
Although the patient’s current magnesium level was only slightly decreased, we decided not to replace it. Her current potassium level was also normal. She was aware of her diagnosis of Gitelman syndrome and was taking potassium and magnesium replacement. Review of the literature reveals that ventricular tachycardia has occurred in patients with Gitelman syndrome when potassium and magnesium levels are low. This potentially fatal arrhythmia must be recognized and treated early.
*Texas Tech University Health Sciences Center, Lubbock Texas. jmayhew@ttusc.edu
