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PWS Molecular Diagnosis

How to request the free molecular test

Free Test by IFF/FIOCRUZ

SPW Brasil and IFF/FIOCRUZ offer free molecular testing for patients with clinical suspicions.

IFF/FIOCRUZ is the first Reference Center for People with Rare Diseases in Rio de Janeiro State.

Referral Criteria

Individuals with the following clinical characteristics should be referred for genetic evaluation:

Birth to 2 years

  • Hypotonia with sucking difficulty

2 to 6 years

  • Hypotonia with history of sucking difficulty
  • Global developmental delay

6 to 12 years

  • Hypotonia with history of sucking difficulty
  • Global developmental delay
  • Excessive food intake with central obesity

13 years and older

  • Hypotonia with history of sucking difficulty
  • Cognitive impairment
  • Excessive food desire with central obesity
  • Hypothalamic hypogonadism
  • Behavioral problems

Important: To promote early diagnosis in babies, the presence of hypotonia alone is sufficient criterion.

Not sure if you should get tested?

Answer our quick questionnaire to assess if there are signs that indicate the need for investigation.

How to Diagnose

About the Test

The test method we use (MS-HRM) has 99% sensitivity in PWS detection.

The test is conducted through DNA conversion with sodium bisulfite.

ATTENTION: ONLY TESTS REQUESTED BY DOCTORS WILL BE ACCEPTED.

How to Send the Sample

Choose only one type of submission: filter paper OR blood.

Option 1: Filter Paper

  1. 1A healthcare professional must collect 6-8 drops of blood
  2. 2Keep the paper in a clean environment until dry
  3. 3Close the card without touching the sample
  4. 4Insert in plastic envelope
  5. 5Place in paper envelope with documents

Option 2: Blood in Tube

  1. 1No fasting required
  2. 2Store in tube with EDTA (purple cap)
  3. 3Invert tube 3-5 times
  4. 4Collect minimum 3ml
  5. 5Wrap in plastic

Required Documents

  • Mandatory consent form
  • Medical request for methylation test

Shipping Address

Laboratório de Alta Complexidade

IFF/FIOCRUZ

Av. Rui Barbosa, 716 – Flamengo

Rio de Janeiro – RJ – CEP: 22250-020, Brazil

Timeline and Results

Timeline: 3 to 12 weeks.

The Coordination will contact the requesting physician.

If positive, the doctor should guide the family.

Questions or Support

For questions, send an email to pwasdiagnostico.iff@fiocruz.br