A 19-year-old man presented with nausea, vomiting, and diarrhea for 24 hours. His vomitus was non-bloody and non-bilious, and his diarrhea contained neither blood nor mucus. His symptoms were associated with diffuse, cramping abdominal pain. He denied ill contacts, but stated that his symptoms started after eating at a fast food restaurant the day before.
He had no significant past medical history, but had emigrated from Saudi Arabia 18 months before presentation. He was a poor historian, and was unable to provide further details. Review of systems revealed several pertinent positives that helped complete the otherwise minimal history. He reported generalized weakness, increased thirst, hair loss, and a 10-pound weight loss over the past year. The social history was pertinent for frequent binge alcohol drinking, a six pack-per-day smoking habit, and daily marijuana use but no other drug use.
Initial vital signs were temperature 98.3°F, sinus tachycardia at 140 bpm, blood pressure 132/75 mm Hg, respiratory rate 20 bpm, and an oxygen saturation of 98% on room air. Physical exam revealed an anxious, thin, disheveled 19-year-old with dry mucus membranes; he was neurologically intact other than appearing to be mildly confused. His neck was supple with no meningismus, no thyromegaly, or cervical adenopathy; heart was tachycardic but regular, no murmurs, rubs, or gallops; and his lungs were clear bilaterally. His abdomen was diffusely tender to palpation, but no masses or organomegaly were palpated, and no peritoneal signs were present. Repeated vital signs showed a temperature of 101.1°F.
Laboratory evaluation showed a leukocytosis at 17.1 and an otherwise normal CBC, as well as normal chemistry, arterial blood gas, and liver function tests. Urinalysis and urine drug screen were negative, as was the influenza PCR. TSH was <0.008, and free T4 was elevated at 10.2. Chest x-ray was within normal limits. The patient's history, exam, and especially vital signs were felt to be sufficient to indicate advanced imaging. CT chest angiography showed no evidence of a PE, but did show a 2.3 cm relatively low attenuation focus in the superior mediastinum, possibly a thymoma or pericardial cyst as well as a mildly prominent thyroid gland. CT abdomen showed mildly prominent mesenteric and pericecal lymph nodes, which could reflect mild mesenteric adenitis.
Thyroid storm was felt to be the leading diagnosis at this point. The patient was started on IV fluids and Lopressor as well as hydrocortisone and propylthiouracil. He was transitioned to an esmolol drip just prior to his admission to the ICU. Endocrinology was consulted, but unfortunately, the patient left the ICU against medical advice early the next day prior to that evaluation. The patient was lost to follow-up.
Thyroid storm is a potentially fatal endocrine emergency, which represents a diagnostic challenge to the emergency practitioner. It exists on a spectrum of thyroid disease, and can present with a nonspecific symptomatology. The complex presentation with multiple seemingly unrelated symptoms can be confusing for patients and practitioners alike, making every step of the diagnostic process, from the history to the selection and interpretation of confirmatory testing, a profound challenge. And there is no clear cutoff in laboratory results, which confirm the diagnosis; it remains a primarily clinical diagnosis. This case highlights some of these challenges, and serves to reinforce the importance of the oft-underappreciated review of systems as well as a careful physical exam. The ROS helped to fill in the gaps left by the patient's poor history.
Thyroid storm is the feared condition that occupies the most severe end of the thyrotoxicosis spectrum. It is rare, but recognizing and differentiating thyroid storm from non-life-threatening thyrotoxicosis is of great importance: recently reported mortality rates range from 10 to 30 percent. (Thyroid 2012;22:661; Endocrinol Metab Clin North Am 2006;35:663.)
Recent studies have indicated a decrease in incidence, most likely because of improved screening for hyperthyroidism, from 10 percent to up to 5.4 percent of patients admitted for thyrotoxicosis. (Thyroid 2012;22:661; Thyroid 2012;22:1094.)
Female gender and underlying Grave's disease are the most common predisposing factors, and it is thought that the transition from thyrotoxicosis to true thyroid storm usually requires a precipitating event such as infection, surgery, parturition, trauma, or exposure to substances such as amiodarone and radiocontrast dye. (Endocrinol Metab Clin North Am 2006;35:663; Rev Endocr Metab Disord 2003;4:129; Ear Nose Throat J 2002;81:570.)
Thyroid storm is primarily a clinical diagnosis, but the degree of abnormalities in laboratory evaluation can indicate severity of disease, including the extent of end-organ damage. Laboratory analysis alone is not sufficient to differentiate thyroid crisis from thyrotoxicosis; total T3 and T4 concentrations have not been shown to be consistently different in the two disease entities. (Ann Intern Med 1980;93:694.)
Multiple attempts to standardize the diagnosis have been published in the critical care literature, including several scoring systems for severity of symptoms. Perhaps the most widely accepted of these was presented by Burch and Wartofsky in 1993 and later adapted by others; that provided a scoring system accounting for thermoregulatory dysfunction, CNS dysfunction (ranging from agitation and confusion to coma), GI/hepatic involvement, CV dysfunction (tachycardia, arrhythmias, and signs of heart failure), and a history of precipitating event. (Endocrinol Metab Clin North Am 1993;22:263.)
Treatment of thyroid storm is multi-tiered. These patients are critically ill, and require immediate symptomatic control and resuscitation to reverse the common systemic manifestations such as dehydration, arrhythmias, congestive heart failure, and adrenal crisis. IV fluids, external cooling, acetaminophen for antipyresis (salicylates can exacerbate thyroid storm), and stress-dose steroids provide a starting point. (Thyroid 1999;9:359; J Intensive Care Med 2013 Aug 5 [Epub ahead of print].) Next, the treatment is directed at the production and effects of thyroid hormone in a three-pronged approach. First, propylthiouracil (PTU) is administered primarily to inhibit thyroid peroxidase; this decreases the conversion of thyroglobulin to T3 and T4. Current guidelines recommend a 500-1000 mg loading dose followed by 250 mg every four hours. (Endocr Pract 2011;17:456.) The peripheral effect of thyroid hormone is then inhibited with beta-blockade; propranolol and esmolol are commonly used, and have the added benefit of inhibiting peripheral conversion of T4 to T3. Finally, release of pre-existing hormone is blocked with administration of iodine and other medications such as lithium. As a note, iodine should be administered at least 30 minutes after PTU or other thionamides to avoid it serving as a substrate for new hormone production. Iodine therapy is often deferred in the ED for this reason. (Endocrinol Metab Clin North Am 2006;35:663; Endocrinol Metab Clin North Am 1993;22:263.) These patients are critically ill, and are best cared for in an ICU.
Thyroid storm can easily mimic sepsis, pulmonary embolus, and many other potentially critical diagnoses. Our case exemplified the diffuse, nonspecific symptomatology often associated with this disease process, and reinforced the fact that a careful history and review of systems, coupled with a high-degree of suspicion are the best line of defense in making this important diagnosis.