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Editor,—The CESDI study report on sudden unexpected deaths in infancy1 and the paper in this journal by Ward, Platt, et al,2emphasise the importance of thorough investigation of all sudden infant deaths if the true cause is to be found.
The history of an apparent life threatening event emerges as a significant risk factor for sudden unexpected death and this, together with symptoms of ill health including sweating in the 24 hours before death, suggests that death in these cases may be due to a metabolic cause in a vulnerable infant.
Guidelines for management of sudden unexpected death in infants under two years old
- Break the news to parents, explain about the urgency and nature of investigations, and the obligation to inform the coroner, but do not delay taking specimens for metabolic investigations whilst you take a history and examine the baby.
- Inform the coroner and obtain permission to take specimens.
- Blood—Perform a heart stab within 30 minutes of death if possible and preferably not over four hours after. Drop some blood onto blood spot cards directly from syringe (for acyl carnitines). Allow to dry at room temperature. Split the remainder into lithium heparin for metabolic tests spin (store plasma at –20°C); plain bottle (clotted blood) for toxicology spin (store serum at –20°C); blood cultures to incubate at 37°; and consider blood for chromosomes—especially if dysmorphic.
- Urine—Supra pubic aspirate (SPA) of bladder. Divide urine into three plain bottles. For microbiology store in fridge at +4°C; toxicology, spin and freeze supernatant at –20°C; biochemistry, for metabolic tests (amino and organic acids), spin and freeze at –20°C.
- Nasopharyngeal swab (if less than eight hours after death) for virology into transport medium. Any other body fluids, swabs, etc, store at 4°C for microbiology.
- Skin biopsy—Send to a metabolic laboratory in culture medium. Store at 4°C.
- Consider muscle and liver biopsy if there is suspicion of IMD—for example, death of sibling or consanguinity. Contact regional metabolic laboratory for advice.
- Take a full history, including detailed account of the final 24 hours, position of baby when found, clothing worn, intercurrent illness in family members, and smoking habits.
- Complete clinical examination—Look for external marks, bruises or injuries and petechiae, look for skull fracture and in fundus for retinal haemorrhages, record rectal temperature and any other signs of illness.
- Explain to parents about sudden unexpected death in infancy, encourage them to hold the baby and give bereavement support. Give advice about cessation of lactation if necessary.
- Radiology—skeletal survey.
- Check child protection register—particularly important if there are young siblings or a twin.
- Inform general practitioner, health visitor, community child health and hospital records, and cancel all appointments.
- Document all specimens taken, label, and ensure an unbroken chain of evidence for forensic specimens. Record the site from which specimens were taken—for example, cardiac stab, SPA, urine, etc. Remember to date, time, and sign the records as these may become legal documents.
Although inherited metabolic diseases (IMD) are rare because of the reduction in preventable causes following the “back to sleep campaign”, they are now likely to form a higher proportion of all sudden unexpected infant deaths, and accurate diagnosis of an index case could well prevent death in a subsequent sibling.
Factors suggesting IMD include consanguineous parents and previous infant death in the family. Although a history of hypotonia or developmental delay and organomegaly may occur, these disorders can cause death without significant prodromal symptoms and can be precipitated in a previously healthy infant by a stress such as infection. Investigation may be limited at necropsy if suitable specimens are not obtained as soon as possible, blood ideally within thirty minutes and tissue preferably not more than four hours after death. Many metabolic disorders can be diagnosed on blood or urine, but some require fibroblasts or other tissue for analysis. It should be possible to perform a skin biopsy for fibroblast culture in most district hospitals.
The CESDI study acknowledged that lack of information was a major impediment to determining the true cause of death and makes recommendations for investigations and procedures following sudden deaths in infancy. It is disappointing that they make no reference to the collection of specimens or procedures to be followed by staff in the accident and emergency department, or wherever the death is confirmed.
It is important that paediatric residents are aware of the urgency and have a protocol for investigation and collection of specimens that has been agreed with the local coroner. In the West Midlands, we have written guidelines for managing sudden unexpected death in infancy to ensure that vital evidence of IMD, infection, or non-accidental injury is not lost.
The authors gratefully acknowledge the contributions from many colleagues in Birmingham, Walsall, and Wolverhampton to the development of these guidelines.