Validation of a lateral flow immunoassay for the detection of immunoglobulin G/immunoglobulin M antibodies to severe acute respiratory syndrome coronavirus 2-COVID-19 among symptomatic and asymptomatic high-risk OBGYN patients in selected hospitals in Olongapo city and Zambales – A multicenter prospective study
- Author:
Tosca Camille S. Guiao
1
;
Corazon R. Valdez
1
;
Louella P. Aquino
1
;
Daisy Grace Z. Rivera
1
;
Madonna M. Valenzuela
1
Author Information
- Publication Type:Journal Article
- Keywords: Asymptomatic; COVID‑19; Rapid antibody test; Real‑time polymerase chain reaction
- MeSH: Pregnancy
- From: Philippine Journal of Obstetrics and Gynecology 2021;45(1):23-30
- CountryPhilippines
- Language:English
-
Abstract:
Background/Introduction:As the world face health-system shocks from COVID-19, Obstetrician-Gynecologists become perplexed by the uncertainties these bring to the vulnerable pregnant and gynecologic population. The country's capacity for diagnosis via RTPCR consists of only a tiny proportion of the population. With the intent of coming up with a less expensive fast point of care test kits, antibody-based lateral flow assays were developed.
Aims and Objectives:Determine the diagnostic accuracy of a lateral flow immunoassay for the detection IgM/IgG antibodies to SARS-CoV2 using RT-PCR as gold standard among symptomatic and asymptomatic high risk OBGYN population.
Materials and Methods:This is a multicenter cross-sectional prospective study performed on 147 asymptomatic and symptomatic high risk OBGYN patients who underwent both RTPCR and RAT. Test results were entered using a two by two table to compute for the sensitivity (Sn), specificity (Sp), positive and negative predictive value (PPV/NPV), likelihood ratios (LR) comparing RT-PCR with IgM/IgG using Medcalc statistical software.
Results:The RAT for IgG/IgM was not found to be sensitive in both groups. It was able to identify only one of the five patients who had COVID-19 based on RT-PCR. Moreover, the (PPV) was found to be only 20% since only one patient tested positive in the RAT for IgM/IgG that was also positive in the RT-PCR. The (LR+ and LR-) for the symptomatic group was close to 1 implying a slightly higher probability of a true positive compared to that of a false positive test and a negative test result given the absence of the disease respectively. (Sp) and (NPV) of the RAT for IgM/IgG is high for both groups. This means that RAT for IgM/IgG does well in identifying patients who truly do not have COVID-19.
Conclusion:With a very low sensitivity of 5% in this study, RAT for COVID-19 cannot be used for screening purposes. - Full text:PhilippJObstetGynecol45123-763875_001243.pdf
