A Dark Horse Diagnosis
The approach to clinical conundrums by an expert clinician is revealed through the presentation of an actual patient’s case in an approach typical of a morning report. Similar to patient care, sequential pieces of information are provided to the clinician, who is
unfamiliar with the case. The focus is on the thought processes of both the clinical team caring for the patient and the discussant.
© 2018 Society of Hospital Medicine
A 73-year-old man presented to the emergency department in late winter with fevers, myalgias, fatigue, low back pain, and poor oral intake. Four days earlier, he had fallen and hit his head. His partner also noticed a few episodes of confusion in the days leading up to presentation.
The patient’s symptoms are nonspecific. Fevers prompt the consideration of systemic infection, though fevers can also be seen in a broad range of noninfectious processes, including malignancy, vasculitis, autoimmune conditions, endocrinopathies, and drug reaction. The clinical picture warrants prompt and comprehensive evaluation, beginning with further detailed history (current illnesses, exposures, travel, vaccinations, medications, cancer screenings, weight change) and a careful physical examination, which will help guide laboratory testing and imaging.
His past medical history was notable for coronary artery disease for which he underwent coronary artery bypass grafting five years prior, hypertension, hyperlipidemia, diet-controlled type 2 diabetes mellitus, gastroesophageal reflux disease, osteoarthritis leading to chronic knee and hand pain, and a history of mildly low testosterone levels. His medications included hydrocodone and acetaminophen, metoprolol tartrate, omeprazole, topical testosterone gel (prescribed for daily use, used intermittently), and aspirin. He was retired and lived in rural Michigan with his female partner. He previously worked as a truck driver and used to train racehorses. He had quit smoking five years earlier. He denied alcohol or injection drug use.
The patient has significant underlying medical conditions. Considering infectious causes of his symptoms, it is notable that he has no reported immunodeficiency. It would be relevant to know if he has been tested for HIV. His rural residence and work with horses raise the possibility of zoonotic infections, including plague (Yersinia pestis), brucellosis (Brucella species), Q fever (Coxiella burnetti), Rhodococcus equi, or group C or G Streptococci. Information about tuberculosis risk factors, other geographic exposures, recent dental work, and ill contacts might be helpful to elucidate the causes of this nonspecific febrile illness with a possible CNS component. With regard to malignancy, it would be helpful to ask about recent weight loss, lymphadenopathy, and prior cancer screenings. Considering other etiologies, he does not report a history of autoimmune or endocrine conditions. However, it is important to consider a vasculitis, such as giant cell arteritis or polyarteritis nodosa, autoimmune conditions, and endocrinopathies such as thyrotoxicosis. The differential diagnosis for his clinical syndrome remains broad.
Vital signs were temperature 37.3°C, heart rate 88 beats per minute, respiratory rate 18 breaths per minute, blood pressure 105/64 mmHg, and oxygen saturation 93% on room air. Oral examination revealed poor dentition. The heart had a normal rate and regular rhythm with no murmurs, rubs, or gallops, and lungs were clear to auscultation bilaterally. The abdomen was unremarkable. Examination of the back was notable for mild tenderness to palpation over the sacrum. He was oriented to person, place, and time, with intact cranial nerves and a nonfocal neurologic examination. The remainder of his examination was normal. The white blood cell (WBC) count was 11.1 × 103/μL, with 84% neutrophils and 9% bands, hemoglobin 13.6 g/dL, platelet count 54 × 103/μL, sodium 122 mmol/L, potassium 3.3 mmol/L, chloride 89 mmol/L, bicarbonate 21 mmol/L, creatinine 1.64 mg/dL, albumin 2.7 g/dL, alkaline phosphatase 136 U/L, AST 60 U/L, ALT 37 U/L, and total bilirubin 2.1 mg/dL.
