{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T17:25:21Z","timestamp":1780507521866,"version":"3.54.1"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,2,5]],"date-time":"2021-02-05T00:00:00Z","timestamp":1612483200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Methylmalonic acidemia and homocystinuria cobalamin C (cblC) type is the most common inborn error of the intracellular cobalamin metabolism, associated with multisystem involvement and high mortality rates, especially in the early-onset form of the disease. Hemolytic uremic syndrome (HUS) is a rare manifestation and needs to be distinguished from other causes of renal thrombotic microangiopathy. We describe a case of a 3-month-old infant, with failure to thrive, hypotonia and pallor, who developed HUS in the setting of cblC deficit, along with dilated cardiomyopathy, and presented delayed response to optic stimulation in visual evoked potentials, as well as enlarged bilateral subarachnoid spaces and delayed myelination in brain magnetic resonance imaging. Renal damage was reversed, while neurodevelopmental profile and eye contact improved after supplementation with parenteral hydroxycobalamin, oral folic acid, betaine and levocarnitine. Homozygous mutation of c.271dupA in the MMACHC gene was ultimately detected. In this report, we highlight the diagnostic challenges as well as the significance of early recognition and multidisciplinary management of this unusual condition. A brief review of published case reports of early-onset cblC deficit and related HUS is depicted, pointing out the initial clinical presentation, signs of renal damage and outcome, MMACHC gene type of mutations and accompanying extra-renal manifestations.<\/jats:p>","DOI":"10.3390\/children8020112","type":"journal-article","created":{"date-parts":[[2021,2,5]],"date-time":"2021-02-05T08:33:48Z","timestamp":1612514028000},"page":"112","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Hemolytic Uremic Syndrome Due to Methylmalonic Acidemia and Homocystinuria in an Infant: A Case Report and Literature Review"],"prefix":"10.3390","volume":"8","author":[{"given":"Vasiliki","family":"Karava","sequence":"first","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonia","family":"Kondou","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Dotis","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgia","family":"Sotiriou","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Spyridon","family":"Gerou","sequence":"additional","affiliation":[{"name":"Gerou Analysis Medical S.A., Diagnostic-Research Clinics, 546 22 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helen","family":"Michelakakis","sequence":"additional","affiliation":[{"name":"Department of Enzymology and Cellular Function, Institute of Child Health, 115 26 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Euthymia","family":"Vargiami","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina","family":"Economou","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dimitrios","family":"Zafeiriou","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1618-9285","authenticated-orcid":false,"given":"Nikoleta","family":"Printza","sequence":"additional","affiliation":[{"name":"1st Department of Pediatrics, Aristotle University of Thessaloniki, Hippokratio General Hospital, 546 42 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,5]]},"reference":[{"key":"ref_1","unstructured":"Adam, M.P., Ardinger, H.H., Pagon, R.A., Wallace, S.E., Bean, L.J.H., Stephens, K., and Amemiya, A. 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