HPLC Hemoglobin Fractionation Report — Interpretation

Peak Results

Key Finding: Markedly Elevated HbF at 36%

• Newborn: 50–80%
• 6 months: ~8%
• 1 year: <5%
• Adults: <2%

Differential Diagnosis for HbF 36%

What's Missing / Noteworthy

• HbA2 is not reported — on the D-10 HbA2/F program, HbA2 is typically quantified separately. Its absence from the peak table is notable; it may be subsumed into another peak or below detection. A normal HbA2 (<3.5%) + elevated HbF would favor HPFH or δβ-thalassemia over β-thalassemia trait (which raises HbA2 to 3.5–7%).
• The A1a fraction at 41.9% is very high — in adults this is abnormal (normal ~1.5–2.5%). In a newborn, early-eluting peaks behave differently and the A1a window may capture non-specific or modified Hb fractions. This warrants correlation with the patient's age.
• The total area is 23,324 with asterisk (*), suggesting the instrument flagged this run as potentially unreliable or outside calibration range.

Bottom Line

Revised Interpretation — 2-Year-Old Girl

The Critical Abnormality

HPLC Pattern Analysis

Most Likely Diagnosis: β⁺-Thalassemia (Intermedia)

• HbF 20–40% + HbA present (26%) + reduced HbA2 or normal HbA2

"In Black people with β⁺-thalassemia, clinical features are less severe (thalassemia intermedia), and transfusion is usually unnecessary; HbF is 20% to 40%, HbA2 is 2%–5%, and the rest is HbA." — Henry's Clinical Diagnosis, 23rd ed.

Differential Diagnosis

What You Must Do Next

1. CBC with indices — expect microcytic hypochromic anemia (low MCV, MCH), low Hb
2. Serum ferritin + iron studies — to exclude concurrent iron deficiency (which can falsely lower HbA2 and alter the HPLC pattern)
3. Repeat HPLC with HbA2 quantitation — the D-10 HbA2/F program should give HbA2; if missing, rerun or request a dedicated HbA2 program
4. Parental HPLC — essential to establish inheritance pattern (both parents likely carriers)
5. Molecular/DNA testing — confirm the specific β-globin mutation (β⁺ vs β⁰) and determine if compound heterozygosity is present
6. Clinical assessment — check growth, spleen size, Hb level; if Hb <7 g/dL with symptoms, may need transfusion support despite "intermedia" label

Bottom Line

CBC Interpretation — 2-Year-Old Girl

Values at a Glance

Key Findings

1. Severe Microcytic Hypochromic Anemia

• Hb 7.7 g/dL — significantly below the 11.5 g/dL lower limit for age. This is moderate-to-severe anemia.
• MCV 59.4 fL — deeply microcytic (normal for age ~72–86 fL). A drop this profound rules out pure iron deficiency as the sole cause; MCV this low points strongly to thalassemia.
• MCH 17.5 pg — severely hypochromic, consistent with deficient hemoglobin synthesis.
• MCHC 29.4 g/dL — reduced, confirming hypochromia.

2. Elevated RDW-CV (16.6%)

• Indicates significant anisocytosis (variation in RBC size).
• In thalassemia, RDW is typically mildly-to-moderately elevated (unlike iron deficiency, which can raise it more markedly). A value of 16.6% fits well.
• The RDW-SD is paradoxically low-normal (34.6 fL) because the RBC population is uniformly shifted to a very small size — the curve is narrow but left-shifted, which the histogram confirms (tight peak around 60–80 fL).

3. RBC Histogram

4. WBC and Platelet: Normal

• WBC 11.0 — normal for age; mild lymphocyte predominance is physiological at 2 years.
• PLT 344 — normal; reactive thrombocytosis can occur in thalassemia with hemolysis (not prominent here).

Integrated Diagnosis

Urgent Next Steps

1. Check if this Hb is baseline or post-illness — acute infection can drop Hb further
2. Serum ferritin + iron/TIBC — concurrent iron deficiency is common in thalassemia and worsens anemia
3. Reticulocyte count — expect elevated (compensatory erythropoiesis)
4. Peripheral blood smear — expect target cells, tear drops, hypochromic microcytes, nucleated RBCs
5. HbA2 quantitation (separate program or repeat HPLC)
6. Parental CBC + HPLC — both parents should be tested
7. Hematology referral — to decide on transfusion threshold and long-term management (regular transfusion ± chelation vs. hydroxyurea vs. curative stem cell transplant)

If Hb <7 g/dL or symptomatic (pallor, failure to thrive, tachycardia), transfusion should not be delayed.

1. Iron profile (serum ferritin, serum iron, TIBC) — to exclude concurrent iron deficiency
2. HbA2 quantitation (repeat HPLC or dedicated HbA2 program)
3. Reticulocyte count
4. Parental CBC and HPLC (both parents) — for thalassemia trait confirmation
5. Haematology referral for transfusion assessment and long-term management

Corrections Made

Reticulocyte Count Interpretation

Is 1.1% Normal or Abnormal Here?

Step 1 — Corrected Reticulocyte Count

Step 2 — Reticulocyte Production Index (RPI)

Interpretation

What This Means Clinically

Defective β-globin synthesis → excess α-chains precipitate → RBC precursors destroyed in the marrow before reaching circulation → low retic count despite high erythroid activity in the bone marrow

Contrast with Iron Deficiency

Bottom Line

Sebaceous Cyst vs. Epidermal Inclusion Cyst

The Core Issue

"The term 'sebaceous cyst' is a misnomer and should be avoided because these cysts do not involve sebaceous glands, nor do they contain sebum." — Fitzpatrick's Dermatology, 9th ed.

"The only true sebaceous cyst is the steatocystoma. The term 'sebaceous cyst' is best avoided." — Dermatology 2-Volume Set, 5th ed. (Bolognia)

Side-by-Side Comparison

Histological Key Difference

Pilar Cyst (Trichilemmal Cyst) — Often Confused Too

Practical Summary

• In clinical practice, when you see a subcutaneous mobile nodule with a central punctum expressing cheesy material → call it an epidermal inclusion cyst (not sebaceous cyst).
• Reserve "sebaceous cyst" only for steatocystoma, which expresses oily fluid and has no punctum.
• On the histopathology report, the presence or absence of a granular layer is the key to distinguishing all three. — Fitzpatrick's Dermatology, 9th ed., p. 1842–1843