SEVERE HYPOTHYROIDISM LEADING TO RESPIRATORY FAILURE AND BULBAR WEAKNESS: A RARE CASE REPORT

Abstract

SESSION TITLE: Wednesday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/23/2019 09:45 AM - 10:45 AM INTRODUCTION: Hypothyroidism is a rare cause of respiratory muscle dysfunction leading to respiratory failure secondary to hypoventilation. It can also cause decreased central ventilatory response to hypoxia and hypercapnia and obstructive sleep apnea syndrome (1). Dysarthria has also been seen as a presenting symptom of hypothyroidism (2). Here, we report a case of an elderly female who developed signs of bulbar weakness along with respiratory failure attributed to severe hypothyroidism. CASE PRESENTATION: A 73-year old Caucasian female with a past medical history of hypothyroidism presented to the emergency department with complaints of progressive generalized weakness. She experienced ambulatory dysfunction due to motor weakness along with dysphagia, hoarseness of voice and drooling. She was hemodynamically stable. Proximal muscle weakness was noted in bilateral upper and lower extremities. Thyroid examination was within normal limits. Arterial blood gas analysis revealed hypercapnia (partial pressure of CO2 81 mm Hg). Thyroid stimulating hormone (TSH) level was 39.299 IU/mL and free thyroxine 4 level was 0.56 ng/dL. Thyroid peroxidase antibody and thyroglobulin antibody levels were elevated (107 IU/mL and 6 IU/mL, respectively). Inflammatory and connective tissue disease workup was negative. Muscle biopsy was performed which showed non-specific muscle atrophy and did not reveal any pathological features consistent with any neuromuscular disorder. Antibodies for myasthenia gravis were negative. Diagnosis of acute hypercapnic respiratory failure associated with autoimmune hypothyroidism was established. She was placed on non-invasive positive pressure ventilation (NIPPV) with constant monitoring of negative inspiratory force and vital capacity. She was given 125 g of intravenous levothyroxine daily for 5 days which was then transitioned to oral 150 mg levothyroxine. The patient showed significant improvement in her symptoms evident by a decreased requirement of NIPPV and improved ambulation. DISCUSSION: Hypothyroidism can manifest as a severe respiratory failure along with symptoms of bulbar weakness. The severity of the condition demands early NIPPV, like in our case. Recovery in severe hypothyroidism may take a protracted course, sometimes taking weeks to months of hormone replacement therapy (3). An early multidisciplinary approach towards this case is essential for optimal management planning. CONCLUSIONS: To conclude, hypothyroidism should always be considered as a rare cause of respiratory failure with hypoventilation and bulbar weakness. Our case reinforces the importance of early recognition of this condition in order to prevent any patient mortality. Reference #1: Behnia M, Clay AS, Farber MO. Management of myxedematous respiratory failure: review of ventilation and weaning principles. Am J Med Sci. 2000;320(6):368-73. Reference #2: El-Shafie KT. Hypothyroidism presenting with dysarthria. J Family Community Med. 2003;10(2):55-7. Reference #3: Khaleeli AA, Edwards RH. Effect of treatment on skeletal muscle dysfunction in hypothyroidism. Clin Sci (Lond). 1984;66(1):63-8. DISCLOSURES: No relevant relationships by Ankit Agrawal, source=Web Response No relevant relationships by Mehak Bassi, source=Web Response No relevant relationships by Amina Saqib, source=Web Response