What is the interpretation of elevated platelet count, absolute neutrophil count, and iron levels, along with a homozygous MTHFR (methylenetetrahydrofolate reductase) variant in a 5-year-old male patient?

Parent Letter: Laboratory Results Interpretation

Dear Parent,

We have reviewed your child's recent laboratory results and are pleased to report that the findings are reassuring and do not indicate any serious medical condition requiring immediate intervention. Below, I will explain each result and what it means for your child's health.

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Complete Blood Count (CBC) Results

Red Blood Cells and Hemoglobin

• Your child's red blood cell count (4.52), hemoglobin (12.5), and hematocrit (38.2) are all completely normal for a 5-year-old boy 1
• The size and hemoglobin content of the red blood cells (MCV, MCH, MCHC) are also within normal ranges, indicating healthy red blood cell production 1

White Blood Cells

• The total white blood cell count (11.1) is normal for this age group 1
• The absolute neutrophil count is mildly elevated at 6.1 (normal range: 0.9-5.4), which is a very common and typically benign finding in young children 1
• This mild elevation is most often seen with recent or ongoing minor infections, inflammation, or even stress, and does not indicate any blood disorder or serious illness 1

Platelets

• Your child's platelet count is mildly elevated at 491 (normal range: 150-450) 1
• In children, this degree of elevation (between 450-700) is classified as "mild thrombocytosis" and is almost always reactive (secondary) rather than a primary blood disorder 1
• Reactive thrombocytosis occurs in 3-13% of hospitalized children and is extremely common in pediatric practice, typically caused by infection, minor inflammation, or iron-related changes 1
• Primary (essential) thrombocythemia is extraordinarily rare in children, occurring in only 1 per million children, and typically presents with platelet counts exceeding 1,000 1, 2
• No treatment or specific monitoring is needed for this mild elevation, as it will resolve on its own once any underlying trigger (such as a recent illness) resolves 1

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Iron Studies

Iron Levels

• Your child's iron level is mildly elevated at 161 (normal range: 28-147) 3
• The iron saturation (42%) and total iron binding capacity (TIBC) are both normal, which indicates this is not pathological iron overload 3
• Ferritin level is normal at 34, confirming adequate iron stores without deficiency or overload 3
• This pattern of mildly elevated serum iron with normal saturation and ferritin can occur transiently in children and does not indicate hemochromatosis or iron overload disease 3

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Vitamin Levels

Vitamin B12 and Folate

• Vitamin B12 (592) and folate (>20.0) levels are both excellent, well above the ranges needed to prevent deficiency 4, 5
• The methylmalonic acid (165) and homocysteine (5.4) levels are normal, which confirms that your child's body is properly utilizing these vitamins 4, 5

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MTHFR Genetic Testing

What Was Found

• Your child has a homozygous MTHFR C677T genetic variant (meaning two copies of this variant, one from each parent) 6
• This is a common genetic variation found in many healthy individuals and does not represent a disease 3

What This Means Clinically

• The most important finding is that your child's homocysteine level is completely normal at 5.4 (normal range: 0.0-9.0), which is the key functional marker we monitor 4, 5
• The MTHFR C677T variant only increases risk for elevated homocysteine when folate levels are low, but your child has excellent folate levels (>20.0) 5, 6
• Current medical guidelines state that MTHFR variants do not independently increase risk of health conditions in the absence of elevated homocysteine levels 3
• The laboratory report correctly notes that these variants "do not independently increase risk of conditions related to hyperhomocysteinemia in the absence of elevated homocysteine levels" 3

What You Should Do

• Continue ensuring your child eats a balanced diet with adequate folate-rich foods (leafy greens, fortified cereals, beans, citrus fruits) 5, 6
• No medication, supplements, or special treatment is needed at this time given the normal homocysteine and excellent folate levels 3
• Periodic monitoring of homocysteine levels may be considered during routine check-ups, particularly during adolescence and adulthood 3
• If your child ever requires chemotherapy with methotrexate (a folate-based medication), physicians should be informed of this MTHFR genotype 3

Important Clarifications About MTHFR

• MTHFR variants are NOT a diagnosis of "MTHFR disease" – they are common genetic variations 3
• Guidelines do not recommend MTHFR testing for evaluation of blood clots or pregnancy complications due to limited evidence of clinical utility 3
• Many online sources provide misleading information about MTHFR variants; please rely on evidence-based medical guidance from your child's healthcare providers 3

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Summary and Recommendations

Your child's laboratory results show:

• Normal red blood cells, hemoglobin, and overall blood counts 1
• Mildly elevated platelets and neutrophils, which are common benign reactive findings in children that require no treatment 1
• Mildly elevated serum iron with normal iron saturation and ferritin, indicating no iron overload disease 3
• Excellent vitamin B12 and folate levels with normal homocysteine, confirming proper vitamin metabolism 4, 5
• MTHFR C677T homozygous variant that is not causing any functional problems given the normal homocysteine level 3, 5

Recommended follow-up:

• No immediate action or treatment is needed 1
• Continue routine well-child care with your pediatrician 1
• Maintain a healthy, balanced diet rich in folate-containing foods 5, 6
• Consider rechecking complete blood count in 2-3 months if your pediatrician recommends, to confirm resolution of the mild platelet and neutrophil elevations 1

Please feel free to discuss any questions or concerns with your child's pediatrician. These results do not indicate any serious medical condition and are overall very reassuring.

Sincerely,

Medical Consultant