GetTheDiagnosis.org

Welcome, guest.
Login or Sign up to edit.

Add an entry

Search:
 

Tools

Add a finding for this diagnosis

Add prevalence for this diagnosis

Switch to calculator mode to see positive predictive value

Switch to sensitivity and specificity

Sort findings by Tag

Sort findings by Differential Diagnosis

Jump To

Good Positive and Negative Likelihood Ratios

Poorly Diagnostic Findings

Findings With Unspecified Accuracy

Hepatitis C: Likelihood Ratios

Introduction: None written.

[Edit Diagnosis] [Merge dx] [Add prevalence]

Tags: Hepatic Infection Tag this Diagnosis.

The likelihood ratios of findings for Hepatitis C are listed below. See the left navigation bar to change the display.

Good Positive and Negative Likelihood Ratios

Finding +LR-LR Comments, Study
HCV Ab RIBA Edit 15.70.1

RIBA (recombinant immunoblot assay), vs HCV PCR

RIBA is not intended to be used as a screening test but rather as a confirmatory test. In addition, note that there are 3 outcomes of RIBA: positive (>= 2 antigens reactivity), intermediate (1 antigen reactive), or negative. Intermediate RIBA does carry a higher PPV than negative but lower than a positive test.

Study: J Clin Microbiol 1992 Aug;30(8):2145-9. PMID 1323578

Anti-HCV Ab Edit 13.10.1

first-generation enzyme immunoassay, vs HCV PCR

Second generation tests are more sensitive (~95%) and reportedly more specific - PPV in high risk pool ~88% or 50% in lower risk pool.

The mean time to seroconversion improves with the generation (16 wk with 1st gen, 10wk with 2nd gen, and 8wk in 3rd gen) per UpToDate (http://www.uptodate.com/online/content/topic.do?topicKey=heptitis/8251).

Study: J Clin Microbiol 1992 Aug;30(8):2145-9. PMID 1323578

Hepatology 1997 Sep;26(3 Suppl 1):43S-47S. PMID 9305663

Poorly Diagnostic Findings

Finding +LR-LR Comments, Study
Elevated Serum Transaminases Edit 1.20.6

vs RIBA gold standard

Study: J Clin Microbiol 1992 Aug;30(8):2145-9. PMID 1323578

Findings With Unspecified Accuracy

Finding +LR-LR Comments, Study
HCV RNA Edit No accuracy specified.

now considered the "gold standard" - though note that some patients can have +ELISA and negative RNA PCR. In these patients, RIBA should be done to confirm past/current infection.

Study: UpToDate http://www.uptodate.com/online/content/topic.do?topicKey=heptitis/8251