Details of 4 Patients With Bacterial Reference Standard Outcomes That Were Classified as Viral by Host-Signature Assay (False-Negatives)

Assay ScoreSexAge, yDischarge DiagnosisCountryMax TemperatureHospitalization Duration, dABXMicrobiologyClinical DetailsUnanimous Adjudication
5F2.9UTIIL39°2CephalexinEscherichia coliPresented with 5-d history of fever without dysuria. On physical examination, no focus of infection. Two serial midstream urine specimens obtained. In first urinalysis, pyuria (8–10 leukocytes), no nitrites. In second, large number of leukocytes, no nitrites. Urine culture with E coli, 100 000 CFU/mL. Kidney ultrasound within normal limits.Yes
7F7FWSIL39°0NoneBartonella henselaePresented with a 5-d history of fever and unilateral axillary pain. Lymphadenopathy observed on same side as axillary pain. Was scratched by the family cat (no record of location of scratches). On physical examination, erythematous tonsils with exudate. Throat culture negative for GAS. A respiratory viral PCR analysis was not performed. Positive serology for BH (IgM+, IgG−). Negative serology for EBV and CMV.Yes
33F8LRTICH38°0β lactam antibioticsMycoplasma pneumoniaePresented with a 6-d history of fever and cough. On physical examination, no focus of infection. Chest radiograph: RLL infiltrate with pleural effusion. Nasopharyngeal PCR positive for MP. No growth in blood culture.No
10F1.5FWSCH40.2°UnknownCefuroximeNonePresented with a 1-d history of fever and apathy. Initial physical examination revealed no focus of infection. The patient had a previous abnormal otoscopy and a diagnosis of AOM 2 wk before the current ED visit, but in the current ED visit, the otoscopy was reported normal. Tympanocentesis was not performed. Laboratories with leukocytosis and elevated PCT (>6).No
Note: Because of the previous AOM history, a technical error was made whereby AOM was written as discharge diagnosis on eCRF given to expert panel.a
  • The discharge diagnosis was the diagnosis recorded by the attending clinician at discharge (and was not modified in light of data accrued after discharge), ABX, antibiotics; AOM, acute otitis media; BH, Bartonella henselae; CFU, colony forming units; CH, Switzerland; CMV, cytomegalovirus; eCRF, electronic case report form; EBV, Epstein Bar virus; FWS, fever without source; GAS, group A streptococcus; Ig, immunoglobulin; IL, Israel; LRTI, lower respiratory tract infection; MP, Mycoplasma pneumoniae; PCR, polymerase chain reaction; RLL, right lower lobe; UTI, urinary tract infection.

  • a To ensure conservative estimation of assay performance, this patient was retained in the performance analysis.