Hantavirus Pulmonary Syndrome Differential Diagnoses

Updated: Jan 15, 2019
  • Author: David J Cennimo, MD, FAAP, FACP, AAHIVS; Chief Editor: Michael Stuart Bronze, MD  more...
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DDx

Diagnostic Considerations

Drug-induced noncardiac pulmonary edema

An appropriate ingestion history of medications that are associated with noncardiac pulmonary edema may differentiate drug-induced noncardiac pulmonary edema from Hantavirus pulmonary syndrome (HPS).

Patients with cardiac pulmonary edema usually have a left ventricular S3 gallop rhythm and often have cardiomegaly upon physical examination, which is not the case with HPS.

Acute respiratory distress syndrome

In contrast to HPS, the distribution of the infiltrates associated with acute respiratory distress syndrome (ARDS) observed on chest radiographs is peripheral rather than central. In addition, pleural effusions are common in HPS but are not a feature of ARDS.

HPS is accompanied by perihilar cuffing, earlier appearance of interstitial edema (Kerley B lines), and pericardiac haziness (fuzzy heart sign), which are characteristic of HPS and are not found with ARDS.

Pneumonic plague

Patients with pneumonic plague are critically ill with hemoptysis, which is not a feature of HPS. Pneumonic plague occurs in the setting of an outbreak of antecedent bubonic plague. Patients with HPS are less ill and have no adenopathy suggesting preceding or concomitant pneumonic plague.

Atypical community-acquired pneumonias

Among the nonzoonotic atypical pneumonias, Legionnaires disease may resemble HPS. Levels of serum transaminases may be mildly elevated in patients with Legionnaires disease and in those with HPS. Relative bradycardia uniformly accompanies Legionnaires disease but not HPS. Gastrointestinal symptoms, particularly diarrhea, may be observed in both. Severe renal insufficiency is uncommon in HPS and is unusual in Legionnaires disease. Cardiopulmonary collapse frequently occurs in HPS and seldom complicates Legionnaires disease, except in the terminal stages.

Tularemia and Q fever are zoonotic atypical pneumonias that are in the differential diagnoses of HPS. However, the vectors are different for these zoonotic infections. Contact with sheep or parturient cats is the usual epidemiological antecedent for Q fever pneumonia. Similarly, contact with deer, rabbits, or deer flies is the usual history suggesting tularemia. Symptoms common to Q fever, tularemia, and HPS are headache and myalgias. Q fever may feature splenomegaly and relative bradycardia, which are findings not observed in HPS. Bilateral hilar adenopathy and bloody pleural effusion characterize tularemic pneumonia and are not associated with HPS.

Viral influenza

Influenza begins abruptly, with patients often recalling the exact minute and/or hour they became acutely ill. A dry nonproductive cough and a sore throat, usually accompanied by rhinorrhea, characterize influenza. These are not features of HPS. Headache and myalgias are common in both infections.