Published online Mar 26, 2020. doi: 10.12998/wjcc.v8.i6.1137
Peer-review started: November 14, 2019
First decision: December 23, 2019
Revised: December 31, 2019
Accepted: January 19, 2020
Article in press: January 19, 2020
Published online: March 26, 2020
Pulmonary hypertension (PH) causes significant morbidity and mortality in diverse childhood diseases. However, limited information has been reported to obtain a good understanding of pediatric PH. Gaps exist between genome sequencing and metabolic assessments and lead to misinterpretations of the complicated symptoms of PH. Here, we report a rare case of a patient who presented with severe PH as the first manifestation without significant cardiovascular malformation and was finally diagnosed with methylmalonic aciduria (MMA) after metabolic and genomic assessments.
An 11-year-old female presented with an aggressive reduction in activity capability and shortness of breath for only 4 mo and suffered from unexplained PH. A series of examinations was performed to evaluate any possible malformations or abnormalities of the cardiovascular system and lungs, but negative results were obtained. The blood tests were normal except for manifestations of microcytic anemia and elevated total homocysteine. Computed tomography and magnetic resonance imaging failed to identify any pulmonary diseases. Cardiac catheterization examination identified a small right coronary artery to pulmonary artery shunt and severe PH. During the follow-up, PH progressed rapidly. Then, genome sequencing and metabolic disorder screening were performed, which confirmed a diagnosis of MMA with MMACHC c.80A > G/c and 609G > A mutations. Vitamin B12, betaine and bosentan were then administered as the main treatments. During the 6-mo follow-up, the pulmonary artery pressure dropped to 45 mmHg, while the right ventricle structure recovered. The patient’s heart function recovered to NYHA class II. Metabolic disorder analysis failed to identify significant abnormalities.
As emerging types of metabolic dysfunction have been shown to present as the first manifestation of PH, and taking advantage of next generation sequencing technology, genome sequencing and metabolic disorder screening are recommended to have a more superior role when attempting to understand unclear or aggressive PH.
Core tip: This report describes a case who suffered an aggressive pulmonary hypertension (PH) as her first onset manifestation. Following the routine diagnostic and therapeutic procedure, we failed to address any abnormalities which could explain the origins of PH. However, taking the advantage of metabolic screening and genome sequencing, we achieved the diagnosis of methylmalonic acidemia and revealed that the severe PH is secondary to methylmalonic acidemia, which was not mentioned among several guidelines of PH. Although metabolic and genome screenings have been recommended in guideline, this case brought our reconsideration to the timing for perform metabolic and genomic screenings. So that, we would like to mention that for some aggressive unexplained PH patients who meets the criteria, such screening procedure should be applied in an earlier stage to prevent putting the patients into irreversible conditions.