Sepsis: Your Zebras
The publication and enforcement of sepsis guidelines and bundles has decreased mortality in severe sepsis and septic shock, but we run the risk of defaulting to autopilot when treating our febrile patients and missing other potential fatal diagnoses. What else do you need to keep in mind when evaluating and treating the febrile patient, besides sepsis?
Hear hoofbeats, treat for horses, consider zebras.
Here's a basic back-pocket differential diagnosis for the non-infected febrile patient.
Leukemia, lymphoma, pheochromocytoma
rheumatoid arthritis, systemic lupus erythematosus
In patients with lupus and fever, fever is caused by infection 54%, and caused by a lupus flare 42%
Drug allergy: DRESS syndrome
Drug rash with eosinophilia and systemic symptoms
Fever present in 90% of patients
Most common with antiepileptics, allopurinol, antipsychotics
Anaphylaxis with fever
Excess serotonin -> AMS, tachycardia, hyperreflexia, muscle breakdown and rhabdo. Linezolid, fentanyl, SSRIs
Hunter criteria: SSRI + one of following
Hypertonia, temperature > 38, and ocular or induced clonus.
Tremor and hyperreflexia
Ocular clonus and agitation/diaphoresis
inducible clonus and agitation/diaphoresis
Rx: benzodiazepines, stop the SSRI, cyproheptadine if severe.
Neuroleptic malignant syndrome
AMS, tachycardia, lead pipe rigidity. From dopaminergic antagonists or withdrawal from parkinson’s meds. Also antiemetics can precipitate. Most commonly Haloperidol and fluphenazine
Can cause rhabdomyolysis
Rx: Stop offending agent, supportive care, dantrolene, bromocriptine if severe.
Sympathomimetic toxidrome (amphetamines/MDMA/EtOH withdrawal)
Tachycardia, agitation, hyperthermia, hypertension. Sweating. Dilated reactive pupils.
Anticholinergic toxidrome (tricyclics especially)
Dilated nonreactive pupils, urinary retention, anhidrotic hyperthermia.
Rx: benzodiazepines, physostigmine (but controversial)
Respiratory alkalosis, Non-anion gap metabolic acidosis, anion-gap metabolic acidosis (from lactic acid).
Can cause tinnitus in mild toxicity
Can present as sepsis, DKA in severe toxicity
Rx: bicarbonate, dialysis
Environmental fever from high external temps
Neuro manifestations. Tachycardia.
Death heat stroke (t > 40c) 3000 from 2006-201010
Rx: evaporative + convective cooling, chilled IV fluids: fan over wet body spra
Dantrolene not recommended
Can be set off by neck trauma (in some cases intubation), infection, iodinated contrast.
Fever, diaphoresis, N/V/D, tachycardia > fever are common. Progresses to paranoia, psychosis, and in some cases, status or coma.
Rx: beta blockade, steroids, thyroid hormone inhibition, IV iodide, fluids.
Embolic vs thrombosis vs infarction (much less likely)
"low grade fever" is part of the classic pulmonary embolism triad, but in reality, on 6% of patients have a fever of greater than 38 degrees celsius.
Blood transfusion reaction
Anesthetics (can happen after succinylcholine), hypercarbia, muscle rigidity
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