Pathologists Lancet Kenya has acknowledged that there is a variance between its positive coronavirus results and the negative results from the other labs in some cases where repeat testing has been done.
Lancet’s East Africa CEO Dr. Ahmed Kalebi, however, has insisted that the Sars-CoV-2 PCR tests done at a cost of Sh8,849 are 100 percent sensitive and specific.
This is even as the laboratory comes under scrutiny following claims by a number of Kenyans that the results of the Sars-CoV-2 tests carried out at the facility are not credible.
In a Facebook post, Dr Kalebi said the incident of disparities was not unique and that the facility has been audited by three government institutions. The controversy which has since seen Dr Kalebi appear before Senate Health Committee begun early last month after two women received two sets of results from different labs with one (Lancet) showing they had Covid-19 while the repeat tests (at Nairobi Hospital) indicating that they were negative.
DISCORDANCE IN RESULTS
“We do appreciate the concerns raised by such discordance in results, which we’ve tried to explain scientifically through newsletters to our esteemed clients, medical colleagues taking care of them and the general public. We’ve also shared independent research studies and evaluations which have demonstrated that positive test results from the Seegene Allplex™️ assay (similar to the one used at PLK) can be missed by other assays (such as those used by various labs in Kenya) and this is particularly so for cases that have low viral loads,” he said.
Dr Kalebi, however, insisted that after “an extensive review and audit” the results confirming that the positive results are accurate thus “no false-positive reporting from us.”
The disparities between test results for Covid-19 he added, can arise due to differences in the concentration of material in the sample tested, the sensitivity of the assays used as well as the technical quality processes in the laboratory.
“We conduct quality control checks on all our tests and have also undertaken international external quality assurance (EQA) for Covid-19 to verify the accuracy of our testing,” he added.
“In the past two weeks, the laboratory has undergone investigations and inspections by various government agencies including the National Covid-19 Command Centre and other health regulatory bodies on the matter of Covid-19 testing at our lab.
CLINICAL SENSITIVITY
“Considering the high sensitivity and specificity of the assay we use that has been confirmed at 100 percent clinical sensitivity and 100 percent clinical specificity, it is not surprising that cases of detected viral RNA at our lab end up being called negative with other assays — particularly for those with low viral loads representing late stages of infection that other labs can miss,” added Dr Kalebi in his post.
Kiambu Central MP Jude Njomo whose family had to bury their late mother Margaret Njomo in early June told the Health Committee on Tuesday that the deceased had tested negative only to be told by the Health ministry she was positive.
A repeat test at the Nairobi Hospital, however, returned negative results prompting Mr Njomo to approach the Ministry of Health director-general with the contradictory results.