The 23-year-old youth, when he was admitted to the Government Medical College Hospital, Thiruvananthapuram (MCH), appeared to be a case of septic shock.
All the inflammatory markers – BNP, D-Dimer, CRP, Ferritin, IL-6 – and Trop-T levels (cardiac marker indicative of heart damage) in blood were elevated. He was negative for COVID-19 rapid antigen as well as PCR test.
The possibilities were several, for it could have been leptospirosis or dengue shock syndrome, septic shock, infective endocarditis or tropical fever syndrome… But the turning point was when he tested positive for the IgG antibody test for COVID-19.
“We are aware of the multisystem inflammatory syndrome in children (MIS-C) in the post-COVID period. Though rare, we are now seeing MIS in adults (MIS-A). In two months, we had five cases, all of whom had a similar clinical course. But unlike in children, the outcomes were not all good,” says R. Aravind, Head of Infectious Diseases, MCH.
Even medical literature documents very few cases of MIS-A. The Centers for Disease Control (CDC) had recently published a case series of 27 cases of MIS-A. The September 2020 newsletter of the Clinical Infectious Diseases Society, India also documents three cases of MIS-A in Mumbai.
The CDC report says that adult patients with current or previous SARS-CoV-2 infection can develop a hyper inflammatory syndrome resembling MIS-C. Adults with severe COVID-19 also have the same hyper inflammatory syndrome but these patients generally have respiratory failure also. In contrast, most MIS-A patients do not have respiratory failure or their respiratory symptoms are minimal, says Dr. Aravind.
The patients in the CDC report had cardiovascular, gastrointestinal, dermatologic, and neurologic symptoms without severe respiratory illness. They also had either a positive PCR test (current infection) or positive antibody assay (recent infection) for COVID-19.
“It is easy to miss a diagnosis of MIS-A because it can masquerade as septic shock. It can occur as a continuum of severe COVID-19 or can be a post-COVID affair. MIS-A cases have come from areas about a month after the epidemic peaked and usually happen 20-25 days after the initial infection,” Dr. Aravind says.
Clinicians must maintain a high index of suspicion of MIS-A when patients come with fever, multisystem involvement, high inflammatory markers, and evidence of exposure to SARS-CoV-2 in recent weeks.
Most MIS-A cases will require a COVID antibody assay for confirmation because PCR tests may be negative in a good number. At present antibody assays are not done in many laboratories.
Early administration of immunomodulatory drugs can prevent MIS-A cases from becoming fatal but MIS-A outcomes can often be complicated as most adults would have some underlying issues.
The CDC notes that while the interval between infection and development of MIS-A is unclear, in patients who reported typical COVID-19 symptoms before MIS-A onset, MIS-A was experienced 2-5 weeks late. Also, 30% adults had a positive antibody test for SARS-CoV-2, all of which indicates that MIS-A is probably a post-infectious process.
Doctors suggest that those who had COVID-19 should be very careful during the convalescent phase.