Guidance

Recommended report formats

Updated 10 October 2024

Applies to England

All reports must include a sample date. The full blood count (FBC) must be reviewed and included in the haemoglobinopathy report as it may be the only indication of thalassaemia.

Where decisions are based on information derived from the family origin questionnaire (FOQ) or from FBC parameters from an alternate source, for example from a referring laboratory, it is advisable to include that information on the report. If you are reporting the standard abbreviations, for example HbAS, you must follow the convention for the haemoglobins present to be reported in the order of greatest to least percentage.

You must separate analytical fact from interpretative opinion. The factual results should be given and then a clear conclusion given in full text, which must include recommendations. If a final result cannot be produced within the 3 working day standard for reporting, an interim report, sufficient for the woman’s clinical care and recommending the testing of the baby’s biological father if necessary, must be issued.

If an individual had a blood transfusion and any of the transfused red cells are still present, misleading data and conclusions may result. This is also true for undeclared bone marrow transplants and gene therapy. It is essential that clinicians realise this fact.

Laboratories must have a universal footnote on all haemoglobinopathy results, for example: ‘unless otherwise stated, result assumes no bone marrow transplant, gene therapy or recent transfusion’ or ‘result valid if not transfused and no history of bone marrow transplant or gene therapy’.

Laboratory reporting can be simplified by considering the conditions that are likely to be encountered in the antenatal screening programme. These will comprise:

• those with no evidence of a haemoglobin variant or thalassaemia
• carriers of a haemoglobin variant
• thalassaemia carriers
• homozygote and compound heterozygote conditions

The form of words in the report may differ depending on the local protocols of the screening laboratory. It is possible that the comment about testing the baby’s biological father will not be needed in all laboratories if alternative protocols are used by the screening service to initiate such requests.

The comments to include in reports are displayed as bullet points. The other text is a prompt for the laboratory and should not be reported verbatim.

Care should be taken when reporting coexisting conditions to make sure all risks to the baby are considered when the results of both biological parents are reviewed.

Report format 0

Use Report format 0 for specimens screened by red cell indices only (low prevalence areas)

Report the red cell indices with the comments:

• no evidence of thalassaemia

• not tested for haemoglobin variants as FOQ indicates both biological parents are of low risk family origins

• testing of baby’s biological father not required

Report format 1

Use Report format 1 for no abnormality detected.

Report the red cell indices and other results as appropriate together with the comments:

• no evidence of an abnormal haemoglobin or thalassaemia

• testing of baby’s biological father not required

Report format 2

Use Report format 2 for the following haemoglobin variant carriers: HbS, HbC, HbD, HbE, HbO^Arab and Hb Lepore.

Report the red cell indices, specific sickle test and other results as appropriate together with the comments:

• results consistent with Hb‘V’ carrier (Hb AV)

Where ‘V’ is the variant haemoglobin detected. Where the variant is HbS, the term ‘sickle cell carrier’ is preferred. When indicated, comment on the possibility of coexisting α thalassaemia. Consider the possibility of α⁰ thalassaemia when MCH <25pg and there are high risk family origins for α⁰.

• testing of baby’s biological father recommended

Report format 3a

Use Report format 3a for haemoglobin variant carriers where testing of the baby’s biological father is not required.

Report the red cell indices, specific sickle test and the other results as appropriate together with the comments:

• results consistent with Hb‘V’ carrier (Hb AV) of no known clinical significance

Where ‘V’ is the variant haemoglobin detected. If co-existing α⁰ thalassaemia is suspected (MCH <25pg) then this must be reported appropriately. If FOQ indicates both biological parents are of high risk family origins for α⁰ thalassaemia then the conclusion must be changed to recommend testing of baby’s biological father.

• testing of baby’s biological father not required

Report format 3b

Report format 3b is for haemoglobin variant carriers where testing of the baby’s biological father is required.

Report the red cell indices, specific sickle test and the other results as appropriate together with the comments:

• results consistent with Hb‘V’ carrier (Hb AV)

Where ‘V’ is the variant haemoglobin detected. Report format 3b must be used for variants of clinical significance (not covered in report format 2) or variants of unknown clinical significance. If the variant is unidentified, recommended wording is carrier of unidentified variant. Caution is recommended when ascribing names to haemoglobin variants unless definitive techniques have been used for their identification. When indicated, comment on the possibility of coexisting α thalassaemia. Consider the possibility of α⁰ thalassaemia when MCH <25pg and there are high risk family origins for α⁰.

• testing of baby’s biological father recommended.

Report format 4a

Use Report format 4a for β thalassaemia carriers.

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with β thalassaemia carrier

Comment on possibility of coexisting α⁰ thalassaemia when there are high risk family origins for α⁰.

• testing of baby’s biological father recommended

Report format 4b

Use Report format 4b for possible β thalassaemia carriers.

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with possible β thalassaemia carrier

Comment on possibility of coexisting α⁰ thalassaemia when there are high risk family origins for α⁰. and the MCH is <27pg.

• testing of baby’s biological father recommended

Report format 5a

Use Report format 5a for HPFH.

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with carrier of hereditary persistence of fetal haemoglobin (HPFH)

• testing of baby’s biological father recommended

Report format 5b

Use Report format 5b for δβthalassaemia carrier.

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with δ/β thalassaemia carrier.

Comment on the possibility of coexisting α⁰ thalassaemia if there are high risk family origins for α⁰.

• testing of baby’s biological father recommended.

Report format 6a

Use Report format 6a for possible α⁰ thalassaemia carriers when both the biological mother and the baby’s biological father are of high risk family origins for α⁰.

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with possible α thalassaemia carrier and/or iron deficiency

• FOQ indicates both biological parents are of high risk family origins for α⁰

• testing of baby’s biological father recommended

Report format 6b

Use Report format 6b for HbH disease.

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with HbH disease

• testing of baby’s biological father recommended if he is of high risk family origins for α⁰ thalassaemia

Report format 7a

Use Report format 7a for possible α thalassaemia carriers when either biological parent is not of high risk α⁰thalassaemia family origins (MCH < 25pg).

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with possible α thalassaemia carrier and/or iron deficiency

• testing of baby’s biological father not required as one or both biological parents are of low risk family origins for α⁰ thalassaemia

Report format 7b

Use Report format 7b for possible α thalassaemia carriers (MCH 25 to 27pg)

Report the red cell indices and the other results as appropriate together with the comments:

• results consistent with possible iron deficiency and/or α thalassaemia carrier

• testing of baby’s biological father not required

Report format 8

Use Report format 8 for homozygote and compound heterozygote conditions.

Report the red cell indices, sickle cell solubility test and the other results as appropriate together with the comments:

• results consistent with Sickle cell anaemia (Hb SS), Hb SC disease, Hb SD disease, Hb SE disease, Hb SO^Arab disease, Hb S/Lepore, Sickle/β thalassaemia, Hb variant/β thalassaemia

Or adapt this format appropriately to fit the haemoglobins present. Potential clinically significant conditions must be referred to a consultant haematologist if not already in follow-up. Comment on the risk of coexisting α⁰ thalassaemia if the MCH <25pg and there are high risk family origins for α⁰.

• testing of baby’s biological father recommended

Guidance on referral of samples for DNA

See the Referral guidelines for antenatal screening specimens spreadsheet for a summary of the main genetic risk combinations that require antenatal screening actions, according to the antenatal screening recommendations, and shows which cases require referral of samples for further studies by DNA analysis.

For other haemoglobinopathy combinations, refer results for an expert opinion.