MOLECULAR DIAGNOSTICS: INFLAMMATORY SYNDROME AND COVID-19
Multi-system inflammatory syndrome is the storm that follows COVID-19 waves
By Bruno Larida, MS, MBA
pandemic and move us into a new normal, a troubling new syndrome has emerged. In the spring of 2020, doctors first noted a constellation of symptoms that suggested hyperinflammation and affected multiple organs at once in children, following ex- posure to or infection with SARS-CoV-2. The symptoms are not linked to any other microbial cause. This syndrome was termed multi-sys-
W
tem inflammatory syndrome in children MIS-C.1
rise in adults,2
As similar symptoms began to it prompted nomenclature
that would include adults (MIS-A). At the population level, MIS cases appear to peak approximately one month after waves of elevated COVID-19 cases. While MIS is rare, it can be severe and require
hile vaccines and continued public health measures are helping to control the COVID-19
MIS-C case peaks have occurred within the United States. Each MIS peak has fol- lowed a corresponding COVID-19 peak by approximately four weeks. Prior to the most recent COVID-19 wave in the summer of 2021, a relatively consistent relationship existed between the magni- tude of COVID-19 and MIS-C spikes. But during the summer of 2021, MIS-C cases dropped to their lowest levels compared to COVID-19 cases. Researchers are still unsure why the pattern changed. Sixty-one percent of the CDC’s report- ed MIS-C cases occur in non-Hispanic Black, Hispanic, or Latinx children. Ad- ditionally, similar to how COVID-19 has spread, most reported MIS-C cases are in male patients. Compared to adults and unlike the incidence of COVID-19, the inflammatory syndrome occurs more often in younger patients. The median age of reported cases is 9 years old, and half of the reported cases fall between 5 and 13 years old.
As we noted above, MIS has been more challenging to track in adults since
the Photo 189710742 © Visivasnc |
Dreamstime.com
Multi-system inflammatory syndrome (MIS) is a serious condition as- sociated with COVID-19 in which different organs become inflamed. The syndrome can occur in children and adults.
admission to the ICU. The underlying cause for MIS remains unclear, however, minimizing COVID-19 transmission using well-documented public health measures is a logical path towards better MIS man- agement. In this article, we provide an overview of MIS and how communities can work to curb its prevalence.
MIS in the United States As of November 1, 2021, the Centers for Disease Control and Prevention (CDC) reported approximately 5,000 cases of MIS-C out of approximately six million COVID-19 cases in children.3
So far, four 32 JANUARY 2022
MLO-ONLINE.COM
syndrome can be dif- ficult to discern from other occurrences of COVID-19-related hyperinflammation. In spite of this, it is clear that MIS-A is rare, with only a few hundred reported cases2
as of
this writing. Similar to MIS-C, MIS-A appears to cluster in younger
patients. The median age of MIS-A pa- tients2
between 19 and 34 years old.4
is 21 years old and 50% of cases fall Most MIS-A
cases occur in male, non-white patients.4
MIS around the world Apart from the United States, MIS also has been reported in Europe.5
How severe is MIS? While MIS-C is rarely fatal, most patients experience severe symptoms and require aggressive treatment including ICU care and mechanical ventilation.6
Out of the
5,526 MIS-C cases reported as of Novem- ber 1, 2021, there have been 48 deaths.3 Though severity estimates may be distorted by the difficulties in finding instances in adults, especially if the adult has pre-existing health issues, MIS-A looks to be more lethal than MIS-C. Re- searchers reported that 57% of MIS-A cases were admitted to intensive care, with 47% requiring respiratory support and 7% of patients losing their life.2
Signs and symptoms of MIS Patients with MIS commonly exhibit the following symptoms. • Fever (for four or more days). • Gastrointestinal symptoms includ- ing nausea, vomiting, and diarrhea. In a recent study, a whopping 71% of MIS-C patients reported gastrointes- tinal problems
• Skin rash • Sores in the mouth • Conjunctivitis • Low blood pressure, which may lead to shock
• Heart symptoms including inflamma- tion in the tissue lining the heart and the heart tissue itself. In more severe cases, heart symptoms associated with MIS may lead to heart and kidney failure. Heart failure ac- counts for a large portion of the overall mortality in MIS.
As of this
writing, experts at the World Health Organization (WHO) are unable to determine why cases appear to be con- centrated in North America and Europe. More data will need to become available to fully understand the geographical occurrence of MIS.
What triggers MIS? The cause of MIS is still unclear. As men- tioned above, nearly every case of MIS has been associated with prior SARS-CoV-2 infection or exposure and is usually not the result of some other microbe. In fact, patients consistently show a time course in which MIS symptoms follow several weeks after they themselves tested posi- tive, had COVID-19 symptoms or were exposed to someone who did. MIS cases tend to arise about four weeks after the onset of COVID-19 symptoms. One study looking at what might cause
MIS suggests that an unknown superan- tigen associated with SARS-CoV-2 trig- gers an excessive and abnormal immune
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50
