Case Description
We present a previously healthy 11-year-old male presented with fevers,
dizziness, loss of appetite and new onset petechial rash on his lower
legs with prolonged epistaxis of one-week duration. The family history
was notable for his mother having died due to lupus nephritis. Both his
father and paternal grandfather were symptomatically positive for
COVID-19 infection three weeks prior to his presentation. Initial
laboratory tests were remarkable for anemia and thrombocytopenia.
[Table 1] A review of the peripheral blood smear shown in Figure 1
A. He also exhibited marked abnormalities in hemolysis markers. [Table
1] Direct antiglobulin (DAT) was positive with normal immune
globulins. [Table 1]
A nasopharyngeal swab showed he was COVID-19 positive by RT-PCR, with
elevated SARS-COV-2 IgG antibodies. Inflammatory markers and cytokines
were normal. [Table 1] His troponin I and Brain natrutic peptide
were both highly elevated. [Table 1] A 2D-echocardiogram was
obtained which was significant for ectasia of left main coronary artery
(LMCA) with uniform dilation with a moderately decreased left
ventricular (LV) function.
We therefore suspected him to have MIS-C with likely TTP or Evan’s
syndrome. Due to the family history of SLE and hematuria and proteinuria
on presentation, we investigated for an underlying rheumatologic
disease. The resultant laboratory tests revealed strong positive SLE
serology [Table 1]
Patient was given Intravenous immune globulin (IVIG) for the treatment
of Evan’s syndrome and followed by pulse methylprednisolone. After 48hrs
following IVIG and methylprednisolone with no clinical or laboratory
improvement and also with new neurological symptoms of drowsiness and
headache as well as right upper quadrant (RUQ) pain, we increasingly
considered TTP. Low ADAMTS13 activity and a high inhibitor titer
confirmed the diagnosis. Thereafter patient was immediately started on
plasma exchange (PE), and promptly exhibited an impressive clinical
improvement in under 24 hours. Following 7 sessions of PE, his platelets
count normalized and anemia gradually improved with complete resolution
of hemolysis markers, proteinuria and hematuria. [Table 1] and
[Figure 1B] A repeat DAT following PE was negative. His
echocardiogram also showed normalization of his LV size and function,
resolution of LMCA dilation and now dilation of the right coronary
artery without evidence of aneurysm for which he was started on low dose
aspirin. Patient was transitioned to prednisone and started on
mycophenoloate mofetil and hydroxychloroquine sulfate for SLE control.
Genetic testing was negative for inherited TTP.