Mohd AlKhalifa^1*, Hisham Ali², Anna Prendiville³

¹Paediatric Registrar, MRCPCH UK United Kingdom

²Consultant Paediatrician, University Hospital Waterford

³Paediatric Registrar RCPI, Dublin, Ireland

^*Corresponding Author: Mohd AlKhalifa, Paediatric Registrar, MRCPCH UK United Kingdom.

Abstract
A 14-year-old girl with a restricted diet was admitted to the emergency department following an episode of hematemesis and consistent constitutional symptoms for one month. Hematological examinations revealed pancytopenia with severe macrocytic anemia, leukopenia, and thrombocytopenia. Further tests confirmed powerful vitamin B12 and folate deficiency. Her symptoms improved after beginning vitamin B therapy, and her weight increased. This case report discusses the diagnosis and management of severe vitamin B12 and folate deficiency in children and highlights the potential for similar presentations to aplastic anemia and hemolysis.

Introduction
Megaloblastic anemia is macrocytic anemia characterized by nuclear abnormalities due to impaired DNA synthesis [1]. This condition is rare in children and is often associated with vitamin deficiency or gastrointestinal disease. Severe vitamin B12 deficiency is typically caused by insufficient consumption of animal foods or pernicious anemia, while folate deficiency can be attributed to inadequate dietary intake, poor absorption from the small intestine, increased metabolic requirements, or increased loss [2]. The prevalence of vitamin B12 deficiency varies but may be more common than previously thought, particularly in specific populations [3]. This case presents a 14-year- old girl with a restricted diet who exhibited hematological signs of vitamin B12 and folate deficiency, which were initially confused with aplastic anemia and hemolysis.

Case Presentation
The patient, a 14-year-old girl with a history of a restricted diet and intentional weight loss, was admitted to the emergency department following one episode of hematemesis against a background of dizziness, lethargy, hair thinning, and poor dentition over one month before presentation. Her diet mainly consisted of fast food without fruits, vegetables, or substantial meat consumption. In the past year, she had intentionally lost weight. Physical examination revealed pallor and hematological investigations showed severe macrocytic anemia, pancytopenia, and signs of hemolysis. A peripheral blood smear revealed abnormal cells and hyper-segmented neutrophils. After ruling out other causes, these findings were attributed to severe vitamin B12 and folate deficiency.

Investigation
The patient's blood work upon admission revealed the following:
Hemoglobin: 6.2 g/dL (11.5-15.5)
Mean corpuscular volume (MCV): 104.3 fL (77.0-95.0)
White blood cell count: 3400/µL (5.0-19.0)
Neutrophil count: 1660/µL (3.0-9.0)
Platelet count: 120 000/mm3 (180-400)
Serum vitamin B12: 125pg/mL (197–771)
Folic acid: 2pg/mL (3–26)

Peripheral blood smear showed teardrop cells, anisocytosis, macrocytosis, schistocytes, hyper-segmented neutrophils, bite cells, and neutropenia. Additional tests were conducted to exclude other differential diagnoses.

Management
The patient was managed with intramuscular vitamin B12 (1mg every alternate day for 2 weeks), folic acid (5mg/day), and a daily multivitamin supplementation. She received education from a pediatric dietitian and was also treated for her anemia with a red cell transfusion, which resolved her persistent tachycardia.

Outcome and Follow-Up
The patient reported improved well-being a few days after the commencement of the treatment. Follow-up investigations revealed significant improvements in her blood work:
Hemoglobin: 9.1g/dL (11.5-15.5)
Mean corpuscular volume (MCV): 99.1 fL (77.0-95.0)
White blood cell count: 4800/µL (5.0-19.0)
Neutrophil count: 2800/µL (3.0-9.0)
Platelet count: 220 000/mm3 (180-400)
Serum vitamin B12: 250pg/mL (197–771)
Folic acid: 5.5pg/mL (3–26)

Her hair regained vitality and gained weight after re-introducing a balanced diet with fruits, vegetables, and lean meats. Moreover, her oral health improved, and the recurring episodes of hematemesis ceased. She was discharged with advice for follow-up consultations with a hematologist and a pediatric dietitian.

Discussion
This case highlights the importance of considering nutritional deficiencies, particularly vitamin B12 and folate deficiency, in pediatric patients with pancytopenia, macrocytosis, and signs of hemolysis. Vitamin B12 deficiency has diverse clinical manifestations and may present with various hematological, gastrointestinal, psychiatric, and neurological symptoms [5]. In such cases, dietary history can provide valuable insights and should be noticed. A study of 201 patients with documented cobalamin deficiency revealed that hematological signs, including macrocytosis and hyper-segmented neutrophils, are often present, and a high index of suspicion is required for diagnosis [4]. Furthermore, this case underscores the significance of a balanced diet for overall health, especially in growing adolescents. The treatment of vitamin B12 deficiency can be effectively managed through either oral or intramuscular administration, depending on the specific needs and context of the patient [6].

Conclusion
Physicians should have a high index of suspicion for megaloblastic anemia in children with a history of dietary restrictions and present with hematological abnormalities. A thorough dietary history and early diagnosis can prevent severe complications, and effective management can ensure an excellent prognosis.

Acknowledgements
We wish to thank the medical team, especially the paediatric haematologists and dietitians, who contributed to the successful management of this case. Their combined expertise was essential in ensuring a positive outcome for the patient.

Conflicts of Interest: The authors declare no conflicts of interest.

References

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