OSCE: Thalassemia Interpretation & Counseling Using the SPIKES Protocol
- Mayta
- Mar 21
- 7 min read
1. Introduction
Thalassemia is a hereditary hemoglobin disorder characterized by reduced (or absent) production of one or more globin chains. In Southeast Asia—particularly in Thailand—there is a high prevalence of both alpha- and beta-thalassemia variants, as well as other hemoglobinopathies such as Hemoglobin E (HbE) and Hemoglobin Constant Spring (Hb CS).
In an Objective Structured Clinical Examination (OSCE), you may be asked to:
Interpret abnormal hemoglobin electrophoresis results suggestive of a thalassemia syndrome.
Counsel the patient (or parents, in the case of a child patient) regarding the diagnosis, inheritance patterns, prognosis, treatment options, and, if relevant, the possibility of pregnancy termination for severe cases.
Use a structured approach—like the SPIKES protocol—to deliver potentially distressing news in a compassionate and clear manner.
This guide provides a concise but comprehensive overview of:
Thalassemia interpretation (focusing on beta- and alpha-thalassemia).
Next steps and management if Thalassemia Major is suspected.
A practical framework (SPIKES Protocol) to counsel and break bad news in an OSCE or real-life setting.
2. Basic Overview of Thalassemia
2.1 Beta-Thalassemia
Normal Genotype: β/β (two functional beta genes).
Beta-Thalassemia Trait (Minor): β/β⁰ or β/β⁺ (one mutated beta gene, one normal).
Hemoglobin Electrophoresis:
HbA2 > 3.5% (key hallmark)
Mildly ↑HbF
Mostly normal HbA
Clinical: Mild or no anemia with microcytosis (low MCV).
Beta-Thalassemia Major: β⁰/β⁰, β⁺/β⁺, or β⁰/β⁺ (two mutated or non-functional beta genes).
Hemoglobin Electrophoresis:
Little or no HbA
Predominantly HbF
Variable HbA2
Clinical: Severe anemia requiring regular transfusions.
2.2 Alpha-Thalassemia
Normal Genotype: αα/αα (four functional alpha genes in total).
Alpha-Thal-2 Trait: -α/αα (one gene deletion).
Often very mild or no anemia; normal or slightly low MCV.
Alpha-Thal-1 Trait (Cis Deletion): --/αα.
Alpha-Thal-1 Trait (Trans Deletion): -α/-α.
HbH Disease: Three alpha gene deletions (e.g., --/-α).
Moderately severe anemia, detection of HbH (β4) on special stain.
Hb Bart’s Hydrops Fetalis: Four alpha gene deletions (--/--).
Usually lethal in utero or shortly after birth, predominantly Hb Bart’s (γ4) in neonates.
2.3 Other Common Hemoglobin Variants in Southeast Asia
HbE: Mutation in the beta chain causing variant hemoglobin.
HbE Trait: ~25–40% HbE + remainder mostly HbA.
HbEE: ~85–95% HbE + variable HbF, little/no HbA.
HbE/β-Thalassemia: Severity ranges from mild to severe depending on whether mutation is β⁰ or β⁺.
Hb Constant Spring (α^CS): Abnormal stop codon in the alpha-globin gene leading to an elongated alpha chain. It can worsen alpha-thalassemia if combined with gene deletions.
3. Hemoglobin Electrophoresis Interpretation (Quick Reference)
Diagnosis | Typical Hb Pattern | Clinical Severity |
Normal | HbA > 95%, HbA2 1.5–3.5%, HbF < 2% | No anemia |
β-Thalassemia Trait | ↑HbA2 (>3.5%), ± mild ↑HbF, mainly HbA | Mild microcytosis |
β-Thalassemia Major | Near absent HbA, ↑↑HbF (often >90%), ±HbA2 | Severe anemia, transfusion-dependent |
HbE Trait | HbE ~ 25–40%, remainder HbA | Mild |
HbE/β-Thalassemia | Combination of HbE + ↑HbF, ± small HbA | Mild to severe |
HbH Disease (α-thal) | Detectable HbH (β4) on electrophoresis (--/-α) | Moderate to severe |
Hb Bart’s Hydrops | Mainly Hb Bart’s (γ4) at birth (--/--) | Lethal |
4. Next Steps if Thalassemia Major is Suspected
Confirm the Diagnosis
CBC: Typically severe microcytosis (MCV < 70 fL), low MCH, high RBC count (relative to degree of anemia).
Hemoglobin Electrophoresis: High HbF, near-absent HbA (for β-thal major).
DNA Analysis: Particularly useful for alpha-thalassemia or to confirm specific β-thal mutations.
Assess Severity and Complications
Regular Transfusion Requirement: Beta-thalassemia major patients often need life-long transfusions to maintain adequate hemoglobin levels.
Iron Overload: Monitor ferritin, liver iron concentration (MRI) to evaluate need for iron chelation.
Genetic Counseling
Mendelian Risks: Each child of two carrier parents (β-thal trait or α-thal-1 trait) has a 25% chance of inheriting the severe form.
Prenatal Diagnosis: Chorionic villus sampling (CVS) or amniocentesis to determine if the fetus has thalassemia major or hydrops fetalis.
Discuss Termination (if legally, ethically, and culturally acceptable): Some parents may opt to terminate the pregnancy if the fetus has Thalassemia Major or hydrops fetalis.
Long-Term Management
Transfusion Program + Chelation Therapy to prevent iron overload.
Hematopoietic Stem Cell Transplantation (HSCT): Potentially curative for β-thalassemia major if a matched donor is available.
5. SPIKES Protocol for Breaking Bad News and Counseling
When delivering serious or potentially distressing information—such as a diagnosis of Thalassemia Major—use the SPIKES protocol:
S – Setting
Ensure privacy (quiet room, no interruptions).
Sit at patient’s (or parents’) eye level.
Ask if they want a family member or friend present.
Minimize distractions (silence phones, etc.).
P – Perception
Explore the patient’s current understanding: “Could you share what you already know about Thalassemia?”
Correct misconceptions gently.
I – Invitation
Ask how much detail they would like: “Would you like me to explain all the details now or start with a summary and answer questions as they come up?”
Respect their preference for information—some want detail, others need an overview first.
K – Knowledge
Give a warning shot before delivering bad news: “I’m afraid I have difficult news…”
Present the information clearly and in small chunks, avoiding medical jargon:
“The test shows that your child likely has Beta-Thalassemia Major, which is a severe form requiring regular treatments.”
Check understanding periodically.
E – Emotions
Pause to observe reaction (shock, silence, crying, anger).
Validate and acknowledge their feelings: “I understand this can be overwhelming.”
Offer empathy and support; hand tissues if they are tearful.
S – Strategy & Summary
Outline management: “This is treatable with regular blood transfusions and iron chelation. Some children may benefit from a stem cell transplant.”
Discuss genetic implications: “Future pregnancies have a 25% risk of this condition if you and your partner are carriers.”
Address Prenatal Diagnosis/Termination if relevant: “Should you consider having more children, there are tests we can do early in pregnancy to see if the baby has this condition. Some parents choose not to continue the pregnancy if the fetus has severe disease.”
Reassure ongoing support: “We will work together, and you are not alone. Our team includes specialists to help you at every step.”
6. Example OSCE Scenario
Scenario:You are a final-year medical student. A couple (both 30 years old) attends the clinic with abnormal alpha-thalassemia screening results. Genetic testing shows each parent has a cis alpha-thal-1 deletion (‘−−/αα‘`--/αα`‘−−/αα‘). This means there is a 25% chance in every pregnancy to have a fetus with Bart’s hydrops fetalis, a lethal form of alpha-thalassemia. They are currently 12 weeks pregnant and concerned about the possibility their fetus may be affected.
S – Setting
Greet them in a private, quiet consultation room.
Sit at eye level, introduce yourself calmly.
Check if they wish to have any family members or friends present for support.
P – Perception
Ask what they already know about alpha-thalassemia and Bart’s hydrops fetalis.
“Could you share what you understand so far about this condition?”
Clarify any misunderstandings gently:
For example: correct the misconception that all alpha-thal carriers have severely affected babies—explain the 25% risk for Bart’s hydrops fetalis specifically.
I – Invitation
“Would you prefer I start with the key points or do you want a detailed explanation about what Bart’s hydrops fetalis is and the next steps?”
Respect how much information they wish to receive at this time.
K – Knowledge
Warning shot: “I’m afraid I have serious news about the baby’s risk.”
Explain: “Both of you have a form of alpha-thalassemia called the ‘cis deletion,’ which leads to a 25% chance in each pregnancy of having a baby with Bart’s hydrops fetalis. This condition is almost always lethal, meaning these babies typically cannot survive to term or die shortly after birth.”
Detail what Bart’s hydrops fetalis involves:
Severe anemia in utero
Massive fluid accumulation (hydrops)
Often leads to miscarriage or stillbirth if not medically intervened (and even with intervention, survival is extremely unlikely)
Check understanding: Pause to ensure they follow the explanation.
E – Emotions
Expect strong emotional reactions: shock, sadness, guilt, confusion.
Acknowledge: “I see how distressing this is. It’s completely normal to feel overwhelmed or upset.”
Validate: “Many couples feel lost or shocked learning about a lethal condition.”
S – Strategy & Summary
Next Steps: Offer prenatal diagnosis to confirm whether this fetus is affected:
CVS (Chorionic Villus Sampling) around 10–12 weeks (could be done immediately, given they are at 12 weeks).
Amniocentesis around 15–18 weeks if CVS is not an option.
Each procedure has a small miscarriage risk, but it provides genetic certainty.
Discuss Options:
If confirmed Bart’s hydrops fetalis, termination of pregnancy is often considered because the condition is typically lethal.
Discuss legal, ethical, and personal beliefs around termination.
Provide Resources:
“We’ll refer you to a maternal-fetal medicine specialist and genetic counselor who can guide you further.”
Psychological support or counseling services.
Summarize: “We suspect a 25% chance the fetus is severely affected. Prenatal testing can tell us for sure. If the fetus does have Bart’s hydrops fetalis, we’ll discuss whether to continue or terminate the pregnancy. We will support you fully in whichever decision you make.”
OSCE Tip: In a timed station, remain empathetic yet concise, and ensure you outline a clear plan.
7. OSCE Pearls
Speak Slowly & Check Comprehension
Parents receiving lethal fetal news can be in shock; pause frequently to confirm they’re following.
Avoid Jargon
Use layman’s terms: “lack of functioning red blood cells” or “baby can’t make enough hemoglobin,” rather than complex genetic descriptions.
Provide Realistic Hope vs. False Reassurance
Bart’s hydrops fetalis is nearly always lethal. Be clear yet compassionate about the outcome, while emphasizing supportive options.
Summarize & Invite Questions
“Please feel free to stop me or ask questions at any point.”
Document Thoroughly
Detail the couple’s understanding, emotional response, your advice, and the plan for follow-up testing or counseling.
8. Conclusion
Bart’s hydrops fetalis represents one of the most severe forms of alpha-thalassemia, typically leading to fetal or neonatal death. In an OSCE scenario (or real-life practice), using the SPIKES protocol ensures you deliver this devastating news in a structured, empathetic manner. Patients must understand the 25% recurrence risk in each pregnancy, the possibility of early prenatal diagnosis via CVS or amnio, and the option of pregnancy termination if the fetus is confirmed to have a lethal condition.
Key Takeaway: Combining a clear explanation of genetic risks and management options with empathetic communication allows patients to feel supported, informed, and empowered when facing a fetal diagnosis as severe as Bart’s hydrops fetalis.
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