AUSTIN (KXAN) — Dr. Alvaro Moreira poured over hundreds of cases trying to get a better understanding of a mystery illness that strikes after a COVID-19 infection. 

His team analyzed and studied Multisystem Inflammatory Syndrome in Children (MIS-C) diagnoses. 

According to the Centers for Disease Control and Prevention, the illness can cause inflammation to different body parts, including the heart. 

Dr. Alvaro Moreira said MIS-C can strike healthy children without warning 3-4 weeks after asymptomatic infection (KXAN/Alvaro Moreira)

“One of the more concerning findings was that… in this very small subset of children who developed this condition, 90% of them received an evaluation of the heart via ultrasound and 54% of those children had abnormal heart function,” Dr. Moreira said. 

He’s a neonatologist with The University of Texas Health Science Center at San Antonio and an assistant professor of pediatrics in the university’s Joe R. and Teresa Lozano Long School of Medicine

The research team looked at 39 studies and reviewed 662 MIS-C cases from around the world between January 1 and July 25. The confirmed cases included newborns to 18-year-olds. Two of the larger studies included data from U.S. cases. Researchers studying link between mystery illness in children and impact on young brains 

“Many of these children will be treated in the intensive care unit with a multidisciplinary team, some of them will require medications to help their heart pump more efficiently,” Moreira said. “When a child or any individual is diagnosed with this condition, they are going to require lifelong imaging of the heart, because this has potentially very serious complications.”

Lifelong complications  

Several months after a MIS-C diagnoses Michelle Jones from Georgetown said she’s still monitoring her daughter, Adeline Shed’s, blood pressure and oxygen levels every day. 

Adeline Shed’s mom said since mid-April her daughter has been sick and battling COVID-19 and MIS-C (KXAN/Michelle Jones)

“She’s still having a hard time breathing and is still really tired and…  just not herself,” Jones said. “Followed up with a cardiologist and he also was concerned about how slow her heart rate was going… and just said to keep an eye on it and monitor at home.”

Jones explained that the 16-year-old spent more than two weeks at Dell Children’s Medical Center over the summer. She said after getting COVID-19 her daughter was then diagnosed with MIS-C. 

She explained that Adeline was showing big improvement once released from the hospital, but earlier this month she had to rush her back to Dell Children’s. 

“She’s just fatigued or she’s very sick to her stomach or she’s having panic attacks because of her heart,” Jones said. 

Jones tells KXAN investigator Arezow Doost that she’s worried about lifelong complications. 

“I hope it’s something that maybe can be fixed with blood pressure medication. Worst case scenario she’s looking at possibly getting a heart monitor, and having to wear that 24/7 and possibly even getting a pace maker put in and that’s for a pretty young age — that’s scary,” Jones said.

Symptoms can surface weeks later

The medical literature review published in, EClinicalMedicine, a journal of The Lancet also found that MIS-C is hitting healthy kids without warning.

“What we have found is that even if you are not symptomatic you can still develop this very severe condition,” Dr. Moreira said. 

He said most children who get COVID-19 will recover without complications. He pointed out, however, that in the research, MIS-C symptoms started surfacing three to four weeks after infection. 

He said if a child has a fever, abdominal pain, skin rash, vomiting, redness to the white of the eye then they need immediate medical attention. 21 cases of inflammatory illness linked to COVID-19 reported in Texas children 

A spokesperson with Texas Department of State Health Services said there are now 22 cases of MIS-C across the state, eight confirmed cases have been reported in Central Texas region. The online data has not been updated yet.

The state says about two-thirds of the cases have been in Hispanic children, and nearly 60% are boys. 

Dr. Moreira said his team found across the world African-American or Afro-Caribbean kids made up about 35% of cases. 

He said another finding included that almost half of patients who had MIS-C had an underlying medical condition, and of those, half of the individuals were obese or overweight.

Moreira explained that the case studies also found that the amount of inflammation in MIS-C is much more severe than two similar pediatric conditions, Kawasaki disease and toxic shock syndrome, which the illness mimics. 

He said therapies commonly used for these pediatric conditions is showing to be working.