Evaluation of Clinical and Laboratory Findings and Diagnostic Difficulties in Children with Vitamin B12 Deficiency

Abstract

Aim: In this study, we evaluated the clinical and laboratory data of healthy children with vitamin B12 deficiency. The benefits of methylmalonic acid (MMA) and homocysteine levels and the difficulties encountered in diagnosing vitamin B12 deficiency were pointed out. Materials and Methods: A total of 70 healthy children whose serum cobalamin levels were below 126.5 pg/ml were included in the study. The age, gender, serum vitamin B12, urine MMA, plasma homocysteine, white blood cell, hemoglobin, thrombocyte, main corpuscular volume (MCV), main platelet volume (MPV), folic acid, and ferritin levels were obtained retrospectively from the hospital’s medical records. The correlation analysis test compared vitamin B12 with MMA and homocysteine. Results: The mean age was 8.21±6.15 years, and vitamin B12 deficiency was found in 6.29% of healthy children. Cobalamin levels ranged from 50-126 pg/ml, with a mean of 102.57±18.97 pg/ml. Urine MMA and serum homocysteine levels were 0.59±0.67 ng/ml and 13.50±0.67 g/dl, respectively. The correlation coefficient value (r) was found to be -0.342 and -0.437, moderately negative for MMA and homocysteine, respectively. MMA levels were normal in 36 patients, and homocysteine levels were normal in 48 patients. Conclusions: Vitamin B12 deficiency is a common micronutrient deficiency in children. The diagnosis of vitamin B12 deficiency can be complex in healthy children who do not display typical laboratory findings, particularly elevated MMA and homocysteine.

Keywords

• Vitamin B12
• Cobalamin
• Methylmalonic Acid
• Homocysteine
• Children

Vitamin B12 Eksikliği Olan Çocuklarda Klinik ve Laboratuvar Bulguların ve Tanısal Zorlukların Değerlendirilmesi

Abstract

Giriş: Vitamin B12 eksikliği saptanan sağlıklı çocukların klinik ve laboratuvar verilerini değerlendirdiğimiz çalışmamızda Vitamin B12 eksikliği tanısında Metilmalonik asit (MMA) ile homosistein düzeylerinin yararlarına ve tanıda karşılaşılan güçlüklere ve dikkat çekildi. Gereç ve Yöntem: Serum kobalamin düzeyleri 126.5 pg/ml'nin altında olan toplam 70 sağlıklı çocuk çalışmaya dahil edildi. Yaş, cinsiyet, serum B12 vitamini, idrar MMA, plazma homosistein düzeyleri, beyaz küre ve trombosit sayıları, hemoglobin, ortalama eritrosit hacmi (Mean Corpuscular Volume, MCV), ortalama trombosit hacmi (mean platelet volume, MPV), folik asit ve ferritin düzeyleri geriye dönük olarak incelendi. Vitamin B12 düzeylerini MMA ve homosistein düzeyleri ile karşılaştırmak için korelasyon analizi kullanıldı. Bulgular: Sağlıklı çocuklarda ortalama yaş 8.21±6.15 yıl olup %6.29'unda B12 vitamini eksikliği saptandı. Kobalamin seviyeleri 50-126 pg/ml arasında değişmekteydi ve ortalama 102.57±18.97 pg/ml olarak saptandı. İdrar MMA ve serum homosistein düzeyleri ortalaması sırasıyla 0,59±0,67 ng/ml ve 13,50±0,67 g/dl idi. Korelasyon katsayısı (r), MMA için -0.342, homosistein için -0.437’ydi ve orta derecede negatif olarak değerlendirildi. 36 hastada MMA seviyeleri, 48 hastada homosistein seviyeleri normaldi. Sonuç: Vitamin B12 eksikliği çocuklarda yaygın bir mikro besin eksikliğidir. Özellikle yüksek MMA ve homosistein düzeyleri gibi tipik laboratuvar bulguları göstermeyen sağlıklı çocuklarda vitamin B12 eksikliğinin teşhisi zor olabilir.

Keywords

• B12 Vitamini
• Kobalamin
• Metilmalonik Asit
• Homosistein
• Çocuk

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