Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2020 May 22;20(1):243.
doi: 10.1186/s12887-020-02130-9.

Pulmonary hypertension in late-onset Methylmalonic Aciduria and Homocystinemia: a case report

Ling-Yi Wen  1 , Ying-Kun Guo  1 , Xiao-Qing Shi  2
Affiliations
Case Reports

Pulmonary hypertension in late-onset Methylmalonic Aciduria and Homocystinemia: a case report

Ling-Yi Wen et al. BMC Pediatr. .

Abstract

Background: Methylmalonic Aciduria and Homocystinemia, cobalamin C (cblC) is an inherited disease of vitamin B12 metabolism with a wide spectrum of clinical manifestations. cblC presenting with pulmonary hypertension (PH) as leading sympotom is rare and easily misdiagnosed because of limited awareness. Timely diagnosis is crucial by the relentless progression without appropriate treatment.

Case presentation: We reported a 12-year-old girl with a 3-year history of progressively reduced activity tolerance and a 3-month history of orthopnea. Metabolic testing revealed increased levels of plasma homocysteine and urine methylmalonic acid. cblC deficiency was subsequently confirmed by genetic testing. The patient was treated with hydroxocobalamin, betaine, folinic acid and levocarnitine for cblC disease. Sildenafil, bosentan, spironolactone and hydrochlorothiazide was administrated for PH and right heart failure. At 3-month follow-up, she had an apparent resolution of dyspnea and cyanosis. Metabolic abnormalities resolved the decrease of plasma homocysteine and urine methylmalonic acid. A right heart catheterization showed a reduced pulmonary pressure.

Conclusions: This case emphasizes the importance of an early diagnosis and initiation of treatment for cblC deficiency. Unexplained PH in children and young adults should prompt metabolic screening for the differential diagnosis.

Keywords: Cobalamin C deficiency; Homocystinemia; Methylmalonic aciduria; Pulmonary hypertension.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Transthoracic echocardiogram demonstrates widened pulmonary artery trunk and pulmonary regurgitation
Fig. 2
Fig. 2
Cardiac magnetic resonance imaging confirms dilated right ventricle with late enhancement at the inferior right ventricular insertion point (arrow)
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Zhou X, Cui Y, Han J. Methylmalonic acidemia: current status and research priorities. Intractable Rare Dis Res. 2018;7(2):73–78. doi: 10.5582/irdr.2018.01026. - DOI - PMC - PubMed
    1. Carrillo-Carrasco N, Chandler RJ, Venditti CP. Combined methylmalonic acidemia and homocystinuria, cblC type. I. Clinical presentations, diagnosis and management. J Inherit Metab Dis. 2012;35(1):91–102. doi: 10.1007/s10545-011-9364-y. - DOI - PMC - PubMed
    1. Komhoff M, Roofthooft MT, Westra D, et al. Combined pulmonary hypertension and renal thrombotic Microangiopathy in Cobalamin C deficiency. Pediatrics. 2013;132(2):e540–e544. doi: 10.1542/peds.2012-2581. - DOI - PubMed
    1. Losito A, Pittavini L, Covarelli C. Thrombotic microangiopathic nephropathy, pulmonary hypertension and nephromegaly: case report of a patient treated with endothelin receptor antagonist. Clin Nephrol. 2012;77(2):164–170. doi: 10.5414/CN106829. - DOI - PubMed
    1. Petropoulos TE, Ramirez ME, Granton J, et al. Renal thrombotic microangiopathy and pulmonary arterial hypertension in a patient with late-onset cobalamin C deficiency. Clin Kidney J. 2018;11(3):310–314. doi: 10.1093/ckj/sfx119. - DOI - PMC - PubMed

Publication types

Substances

Supplementary concepts