Transfusion Medicine

Notification and support for people exposed to the risk of Creutzfeldt-Jakob disease (CJD) (or other prion diseases) through medical treatment (iatrogenically)

BACKGROUND

Creutzfeldt-Jakob disease (CJD) and variant CJD (vCJD) are rare and always-fatal diseases transmissible via certain medical procedures. If a person is exposed to the disease risk through medical treatment, they may need to be notified of this to prevent them passing the risk to others in healthcare settings and to enable additional infection control measures to be put in place for certain procedures. As CJD is incurable, and unable to be screened for or effectively treated, communicating this risk information after an exposure incident may have significant implications for the person at risk, their families/ carers and healthcare professionals. The best ways to notify people of their exposure to the risk of CJD or vCJD, and to support them subsequently, are currently unknown.

OBJECTIVES

To evaluate the effects of interventions to notify and support consumers (patients and their family members or carers) in situations where exposure to the risk of CJD or vCJD has occurred as a result of medical treatment (iatrogenically), on consumer, healthcare provider and healthcare system outcomes.

SEARCH STRATEGY

We searched the Cochrane Consumers and Communication Review Group Specialised Register (10 February, 2009), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1 2009), MEDLINE (OVID SP), EMBASE (OVID SP), PsycINFO (OVID SP), CINAHL (EBSCO Host), Current Contents (OVID SP) and Dissertation Abstracts (Proquest) from start date to February 2009. We searched MEDLINE In-process and Other Non-indexed Citations (OVID SP) and Sociological Abstracts (CSA) in November 2009. We searched reference lists, websites, and contacted consumer groups and experts for details of relevant research.

SELECTION CRITERIA

Randomised and quasi-randomised controlled studies, controlled before-and-after studies and interrupted time series analyses assessing the effects of any intervention to communicate with (notify or support) people exposed to the risk of CJD or vCJD through medical treatment were included. We sought outcomes relevant to consumers, health providers and health services, including both benefits and harms.

DATA COLLECTION AND ANALYSIS

Cochrane reviewTwo authors independently assessed studies for inclusion against selection criteria, and would have applied standard Cochrane review methodology were any studies identified.Thematic synthesisWe also conducted a thematic synthesis by systematically identifying and screening those studies that met the same population, intervention and outcome criteria as the Cochrane review, but that were identified from the broader literature providing evidence on policy implementation and consumer experiences. We systematically extracted and synthesised the data from these studies to produce a thematic synthesis, presented in appendices to this Cochrane review, which assembles evidence on the views, experiences and acceptability of notification and support strategies for people at risk.

MAIN RESULTS

Results of the Cochrane reviewNo studies meeting the study design criteria were identified for inclusion in this Cochrane review.Results of thematic synthesisIn total, 49 studies and pieces of literature meeting the same population, intervention and outcome criteria as the Cochrane review, but identified from the broader literature providing evidence on policy implementation and consumer experiences, were included and formed the basis of a thematic synthesis, and which is presented in appendices to this Cochrane review. The thematic synthesis indicates that ideally communication may be considered as a longitudinal multicomponent programme, ensuring that notification and support are coordinated; that communication is tailored and responsive to need; and that activities to support individual risk communication, such as widespread education and monitoring of access to health care for those at risk, are in place. The thematic synthesis also indicates that poor communication practices may have negative impacts or cause harm, such as discrimination in accessing health care.

AUTHORS' CONCLUSIONS

There is insufficient rigorous evidence to determine the effects of interventions to notify people at CJD or vCJD risk and to support them subsequently, or to identify the best approach to communication in these situations. The thematic synthesis can be used to inform policy and practice decisions for communicating with people at risk in the absence of rigorous evaluative studies.

Implications of prion diseases for dentistry: an update

Prions are normal proteins present in all mammals, especially in the central nervous system (CNS) and lymphoreticular tissue. Their transformation into a highly infectious molecule gives rise to a group of diseases known as transmissible spongiform encephalopathies (TSEs), which cause vacuolar degeneration of gray matter and produce a fatal neurodegenerative disorder. Prion diseases have attracted considerable attention in recent years, and this review of the literature was designed to determine their implications for dentistry, studying the possibility of cross-transmission in the dental office and describing their oral manifestations. The main oral manifestations are dysphagia, dysarthria, paresthesias, dysesthesias, and dysgeusia. The most frequently involved oral tissues are the trigeminal ganglion, posterior third of the tongue, tonsils, and, much less commonly, alveolar nerves, gingiva, and salivary glands. Although no contagion has been reported in the dental setting to date, prions resist the usual dental sterilization systems and transmission of this type of disease remains a potential risk. It is therefore important for dentists to be aware of these diseases, to identify high-risk patients by obtaining an adequate clinical history, and to know the appropriate procedures to be followed.

Successful treatment of severe gastrointestinal bleeding secondary to Crohn disease with recombinant factor VIIa

A 58-year-old man diagnosed with ileocolonic Crohn disease was admitted to the emergency room with massive lower gastrointestinal hemorrhage and hypovolemic shock. Treatment was started with methylprednisolone, metronidazole and omeprazole. Within the next 24 hours, he received a total of 9 U of red blood cell concentrate and 2 U of fresh frozen plasma. Because of persistence of bleeding, hypovolemic shock and life-threatening situation, we started therapy with rFVIIa. One dose of 120 microg/kg and another dose of 120 microg/kg three hours after the first dose were administered as compassionate use, with resolution of bleeding in the next 12 hours. On day 4 the patient was stabilized. We performed a total colonoscopy and intubation of the ileocecal valve that showed patchy deep ulcerations in the rectum with bleeding inflammatory pseudopolyps. Acute gastrointestinal bleeding is an unusual complication in Crohn disease. In this case, the use of recombinant activated factor VIIa controlled the massive gastrointestinal bleeding secondary to Crohn disease and without clinically significant adverse effect. There are few case reports documenting the use of recombinant activated factor VIIa for this type of off-label indication. Clinical trials should be carried out to define the dosage and dose interval schedule of rFVIIa in the treatment of uncontrolled massive gastrointestinal bleeding secondary to Crohn disease.

Paediatric transfusion

The requirements of children undergoing transfusion should be considered as a distinct entity from those of adults. Neonates are particularly vulnerable and there have been concerns over infective or toxic risks to this group. Neonates may also have more acute side-effects as a result of their small blood volume. Most children who are transfused will have a good life expectancy, so long-term side-effects will be more significant than for adults. In Britain, there are a number of transfusion components with neonatal specifications, but there appears to be some confusion, among both medical and laboratory staff, as to the appropriate use of these. Although there are many paediatric guidelines on the use of blood, there is a lack of evidence underlying these. However, there are trends to decreased blood usage in neonates and ongoing studies to investigate the appropriate use of blood for children.

[Diagnosis of acute transfusion reactions]

The erroneous transfusion of AB0-incompatible red cells may result in hemolysis and complement-mediated shock (acute hemolytic transfusion reaction, AHTR), leading to death in less than 10%. The mistake will be detected by re-checking the patient's and the blood product's identity. Evidence of the incompatible transfusion is supplied by serology and, in cases of a fatal outcome, by immunohistochemistry. Differential diagnoses to be distinguished from AHTR are other immunologically mediated events like the most important transfusion-related acute lung injury (TRALI), febrile non-hemolytic transfusion reaction (FNHTR), allergic transfusion reactions, along with a variety of nonimmunologic incidents like transfusion-transmitted bacterial infections, hypervolemia, and other rare events such as citrate reaction, air embolism, and foreign body embolism. If the outcome is lethal, the question of causality has to be answered by a comprehensive evaluation including the clinical data as well as serological, microbiological, autoptic, and histological findings.