Sunday, April 28, 2013

H7N9 Influenza: Most Patients Critically Ill

Troy Brown
Apr 25, 2013

Most of the 82 patients studied who developed H7N9 became critically ill and were epidemiologically unrelated, according to an analysis of data obtained from field investigations of cases that occurred in China before April 17, 2013. Human-to-human transmission between close contacts has not been confirmed but could not be ruled out in 2 families in an analysis by a group of researchers from China and the Centers for Disease Control and Prevention.
Qun Li, MD, from the Public Health Emergency Center in China, and colleagues present their findings in an articlepublished online April 24 in the New England Journal of Medicine.
The researchers defined a confirmed case as one verified by H7N9 virus presence by positive real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR), viral isolation, or serologic testing. Close contacts were observed for 7 days. The investigators obtained throat swabs from symptomatic contacts and tested for the H7N9 virus by real-time RT-PCR.
Among the 82 confirmed cases, the median age was 63 years (range, 2 - 89 years): 38 cases (46%) occurred in patients aged 65 years or older and 2 (2%) in children younger than 5 years. Both children had clinically mild upper respiratory illness. Two suspected cases were also found.
Of the confirmed cases, 73% were male, and 84% were urban residents. Of the 71 patients with available data, 54 (76%) had underlying medical conditions. Cases were reported in 6 areas of China.
Eighty-one patients with confirmed disease (99%) were hospitalized and 17 (21%) confirmed cases, and a single suspected case died of acute respiratory distress syndrome or multiorgan failure. A total of 60 confirmed cases and 1 suspected case remained critically ill as of April 17; 4 patients were discharged from the hospital, and 1 child was never hospitalized.
Animal Exposure
Animal exposure data were available for 77 of the confirmed cases. Of these patients, 59 (77%) had recent animal exposure: 45 (76%) to chickens, 12 (20%) to ducks, and 4 (7%) to swine. The individuals had either worked at or visited a live animal market. These patients also reported exposure to pigeons, geese, quail, wild birds, pet birds, cats, and dogs. History of animal exposure was unclear for the remaining 5 patients, in whom investigations were still ongoing.
The researchers estimated the median incubation period was 6 days in 23 patients for whom detailed data were available.
Of the 1689 close contacts, 1251 completed the 7-day monitoring period. A few (19; 1.5%) developed respiratory symptoms, but they all tested negative for the H7N9 virus.
There were 2 family clusters in which human-to-human transmission could not be ruled out. In one, a brother and his father were in prolonged, close contact with the index case. The father and brother cared for the index case and ate meals together. The index case had contact with live poultry, but the father and brother did not.
In the other family, a father had suspected illness and his daughter had prolonged, close, unprotected contact with him. She was later confirmed to have H7N9 illness. The father had contact with live poultry, but the daughter had no contact with poultry or pigs.
The investigators had data regarding oseltamivir administration for 64 patients, of whom 41 (64%) received oseltamivir starting a median of 6 days after illness onset.
"Although the risk of human-to-human transmission of H7N9 virus appears to be low, the actual risk is currently unknown, and the Chinese national guidelines recommend implementing control measures, such as prompt isolation of the patient, active monitoring of close contacts, and implementation of standard, contact, and droplet precautions by health care personnel in hospitals," the authors write.
"In addition, national guidelines recommend that antiviral treatment with oseltamivir should be administered as soon as possible in patients with suspected or confirmed cases of H7N9 virus infection," they conclude.
N Engl J Med. Published online April 24, 2013.

Thursday, April 11, 2013

Pediatric Skull Fracture -- Is Skeletal Survey Indicated?

Apr 05, 2013

Yield of Skeletal Surveys in Children ≤ 18 Months of Age Presenting With Isolated Skull Fractures

Laskey AL, Stump TE, Hicks RA, Smith JL
J Pediatr. 2013;162:86-89

Study Summary

Assessing the potential for abusive injury in preverbal children is a challenge. Because head trauma is a common occurrence in young children, clinicians often face a dilemma about whether to perform a more extensive evaluation for other evidence of injury when historical "red flags" for abuse are not present.
Methods. This study was a retrospective chart review of patients ≤ 18 months old who had isolated skull fractures when seen at a single pediatric referral center during a 7-year period ending December 31, 2010. For all children, the chief complaint was possible head injury without suspicion of significant intracranial injury. Children were identified from diagnostic codes, excluding those whose skull fractures were identified incidentally or were the result of birth trauma or a verifiable traumatic event such as a motor vehicle crash. Children with intracranial hemorrhage evident on imaging were also excluded, but children with minimal (localized) intracranial hemorrhage associated with the isolated skull fracture were included. The study accounted for demographic features, the type of skull fracture, and the presence of red flags suggestive of abuse, such as conflicting or changing history given by the caregivers, a delay in care (> 72 hours after injury), previous interaction with Child Protective Services, or evidence of other injuries identified on the physical examination. Falls were classified according to distance (≤ 3 feet or > 3 feet).
Findings. A protocol was followed by the emergency department at the referral center whereby most children with isolated skull fractures received skeletal surveys. Of 175 children who presented during the study period and met study criteria, 150 (86%) received a skeletal survey, and 35% of those children had at least 1 red flag in their history or physical examination. The mean age of the children was 5.2 months, and almost two thirds were less than 6 months old. The children were primarily white, with 14% black and 6% Hispanic. About two thirds were publicly insured.
Among children who had a skeletal survey, 9 (6%) had at least 1 additional fracture. Most of the associated fractures were rib, upper-, or lower-extremity fractures. Most skull fractures were simple skull fractures. An additional fracture was found on the skeletal surveys of 13% of children who had at least 1 red flag. The most common red flag was a delay in care, but caregivers being unable to give a history of the injury was also prevalent, as was a changing history.
Laskey and colleagues concluded that performing a skeletal survey on preverbal children with apparent isolated skull fractures identifies additional fractures in 6% of cases. They suggested that because 7 of the 9 cases with additional fractures were in children younger than 6 months old, it may also be reasonable to restrict skeletal surveys to those very young infants. Mobile toddlers who are more likely to demonstrate pain or impaired mobility from a fracture might be a group in which to consider avoiding skeletal surveys if they have a normal physical examination.

Consensus Statement on Concussion in Sport

The 4th International Conference on Concussion in Sport Held in Zurich, November 2012

Br J Sports Med. 2013;47(5):250-258. 
 Section 1: Sport Concussion and its Management
The Zurich 2012 document examines the sport concussion and management issues raised in the previous Vienna 2001, Prague 2004 and Zurich 2008 documents and applies the consensus questions from section 3 to these areas.

Definition of Concussion

A panel discussion regarding the definition of concussion and its separation from mild traumatic brain injury (mTBI) was held. There was acknowledgement by the Concussion in Sport Group (CISG) that although the terms mTBI and concussion are often used interchangeably in the sporting context and particularly in the US literature, others use the term to refer to different injury constructs. Concussion is the historical term representing low-velocity injuries that cause brain 'shaking' resulting in clinical symptoms and that are not necessarily related to a pathological injury. Concussion is a subset of TBI and will be the term used in this document. It was also noted that the term commotio cerebri is often used in European and other countries. Minor revisions were made to the definition of concussion, which is defined as follows:
Concussion is a brain injury and is defined as a complex pathophysiological process affecting the brain, induced by biomechanical forces. Several common features that incorporate clinical, pathologic and biomechanical injury constructs that may be utilised in defining the nature of a concussive head injury include:
  1. Concussion may be caused either by a direct blow to the head, face, neck or elsewhere on the body with an ''impulsive' force transmitted to the head.
  2. Concussion typically results in the rapid onset of short-lived impairment of neurological function that resolves spontaneously. However, in some cases, symptoms and signs may evolve over a number of minutes to hours.
  3. Concussion may result in neuropathological changes, but the acute clinical symptoms largely reflect a functional disturbance rather than a structural injury and, as such, no abnormality is seen on standard structural neuroimaging studies.
  4. Concussion results in a graded set of clinical symptoms that may or may not involve loss of consciousness. Resolution of the clinical and cognitive symptoms typically follows a sequential course. However, it is important to note that in some cases symptoms may be prolonged.

Recovery of Concussion

The majority (80–90%) of concussions resolve in a short (7–10 day) period, although the recovery time frame may be longer in children and adolescents.[2]

Symptoms and Signs of Acute Concussion

The diagnosis of acute concussion usually involves the assessment of a range of domains including clinical symptoms, physical signs, cognitive impairment, neurobehavioural features and sleep disturbance. Furthermore, a detailed concussion history is an important part of the evaluation both in the injured athlete and when conducting a preparticipation examination. The detailed clinical assessment of concussion is outlined in the SCAT3 and Child SCAT3 forms, which are given in the appendix to this document.
The suspected diagnosis of concussion can include one or more of the following clinical domains:
  1. Symptoms—somatic (eg, headache), cognitive (eg, feeling like in a fog) and/or emotional symptoms (eg, lability);
  2. Physical signs (eg, loss of consciousness (LOC), amnesia);
  3. Behavioural changes (eg, irritability);
  4. Cognitive impairment (eg, slowed reaction times);
  5. Sleep disturbance (eg, insomnia).
If any one or more of these components are present, a concussion should be suspected and the appropriate management strategy instituted.

On-field or Sideline Evaluation of Acute Concussion

When a player shows ANY features of a concussion:
  1. The player should be evaluated by a physician or other licensed healthcare provider onsite using standard emergency management principles and particular attention should be given to excluding a cervical spine injury.
  2. The appropriate disposition of the player must be determined by the treating healthcare provider in a timely manner. If no healthcare provider is available, the player should be safely removed from practice or play and urgent referral to a physician arranged.
  3. Once the first aid issues are addressed, an assessment of the concussive injury should be made using the SCAT3 or other sideline assessment tools.
  4. The player should not be left alone following the injury and serial monitoring for deterioration is essential over the initial few hours following injury.
  5. A player with diagnosed concussion should not be allowed to RTP on the day of injury.
Sufficient time for assessment and adequate facilities should be provided for the appropriate medical assessment both on and off the field for all injured athletes. In some sports, this may require rule change to allow an appropriate off-field medical assessment to occur without affecting the flow of the game or unduly penalising the injured player's team. The final determination regarding concussion diagnosis and/or fitness to play is a medical decision based on clinical judgement.
Sideline evaluation of cognitive function is an essential component in the assessment of this injury. Brief neuropsychological test batteries that assess attention and memory function have been shown to be practical and effective. Such tests include the SCAT3, which incorporates the Maddocks' questions[4 5]and the Standardized Assessment of Concussion (SAC).[6–8] It is worth noting that standard orientation questions (eg, time, place and person) have been shown to be unreliable in the sporting situation when compared with memory assessment.[5 9] It is recognised, however, that abbreviated testing paradigms are designed for rapid concussion screening on the sidelines and are not meant to replace comprehensive neuropsychological testing which should ideally be performed by trained neuropsychologists who are sensitive to subtle deficits that may exist beyond the acute episode; nor should they be used as a stand-alone tool for the ongoing management of sports concussions.
It should also be recognised that the appearance of symptoms or cognitive deficit might be delayed several hours following a concussive episode and that concussion should be seen as an evolving injury in the acute stage.

Evaluation in the Emergency Room or Office by Medical Personnel

An athlete with concussion may be evaluated in the emergency room or doctor's office as a point of first contact following injury or may have been referred from another care provider. In addition to the points outlined above, the key features of this examination should encompass:
  1. A medical assessment including a comprehensive history and detailed neurological examination including a thorough assessment of mental status, cognitive functioning, gait and balance.
  2. A determination of the clinical status of the patient, including whether there has been improvement or deterioration since the time of injury. This may involve seeking additional information from parents, coaches, teammates and eyewitnesses to the injury.
  3. A determination of the need for emergent neuroimaging in order to exclude a more severe brain injury involving a structural abnormality.
In large part, these points above are included in the SCAT3 assessment.

Concussion Investigations

A range of additional investigations may be utilised to assist in the diagnosis and/or exclusion of injury. Conventional structural neuroimaging is typically normal in concussive injury. Given that caveat, the following suggestions are made: Brain CT (or where available an MR brain scan) contributes little to concussion evaluation but should be employed whenever suspicion of an intracerebral or structural lesion (eg, skull fracture) exists. Examples of such situations may include prolonged disturbance of the conscious state, focal neurological deficit or worsening symptoms.
Other imaging modalities such as fMRI demonstrate activation patterns that correlate with symptom severity and recovery in concussion.[10–14] Although not part of routine assessment at the present time, they nevertheless provide additional insight to pathophysiological mechanisms. Alternative imaging technologies (eg, positron emission tomography, diffusion tensor imaging, magnetic resonance spectroscopy, functional connectivity), while demonstrating some compelling findings, are still at early stages of development and cannot be recommended other than in a research setting.
Published studies, using both sophisticated force plate technology, as well as those using less sophisticated clinical balance tests (eg, Balance Error Scoring System (BESS)), have identified acute postural stability deficits lasting approximately 72 h following sports-related concussion. It appears that postural stability testing provides a useful tool for objectively assessing the motor domain of neurological functioning, and should be considered as a reliable and valid addition to the assessment of athletes suffering from concussion, particularly where the symptoms or signs indicate a balance component.[15–21]
The significance of Apolipoprotein (Apo) E4, ApoE promoter gene, Tau polymerase and other genetic markers in the management of sports concussion risk or injury outcome is unclear at this time.[22 23]Evidence from human and animal studies in more severe traumatic brain injury demonstrates induction of a variety of genetic and cytokine factors such as: insulin-like growth factor 1 (IGF-1), IGF binding protein 2, Fibroblast growth factor, Cu-Zn superoxide dismutase, superoxide dismutase 1 (SOD-1), nerve growth factor, glial fibrillar acidic protein (GFAP) and S-100. How such factors are affected in sporting concussion is not known at this stage.[24–31] In addition, biochemical serum and cerebral spinal fluid biomarkers of brain injury (including S-100, neuron-specific enolase (NSE), myelin basic protein (MBP), GFAP, tau, etc) have been proposed as a means by which cellular damage may be detected if present.[32–38] There is currently insufficient evidence, however, to justify the routine use of these biomarkers clinically.
Different electrophysiological recording techniques (eg, evoked response potential (ERP), cortical magnetic stimulation and electroencephalography) have demonstrated reproducible abnormalities in the postconcussive state; however, not all studies reliably differentiated concussed athletes from controls.[39–45] The clinical significance of these changes remains to be established.

Neuropsychological Assessment

The application of neuropsychological (NP) testing in concussion has been shown to be of clinical value and contributes significant information in concussion evaluation.[46–51] Although cognitive recovery largely overlaps with the time course of symptom recovery in most cases, it has been demonstrated that cognitive recovery may occasionally precede or more commonly follow clinical symptom resolution, suggesting that the assessment of cognitive function should be an important component in the overall assessment of concussion and, in particular, any RTP protocol.[52 53] It must be emphasised, however, that NP assessment should not be the sole basis of management decisions. Rather, it should be seen as an aid to the clinical decision-making process in conjunction with a range of assessments of different clinical domains and investigational results.
It is recommended that all athletes should have a clinical neurological assessment (including assessment of their cognitive function) as part of their overall management. This will normally be performed by the treating physician often in conjunction with computerised neuropsychological screening tools.
Formal NP testing is not required for all athletes; however, when this is considered necessary, it should ideally be performed by a trained neuropsychologist. Although neuropsychologists are in the best position to interpret NP tests by virtue of their background and training, the ultimate RTP decision should remain a medical one in which a multidisciplinary approach, when possible, has been taken. In the absence of NP and other (eg, formal balance assessment) testing, a more conservative RTP approach may be appropriate.
NP testing may be used to assist RTP decisions and is typically performed when an athlete is clinically asymptomatic; however, NP assessment may add important information in the early stages following injury.[54 55] There may be particular situations where testing is performed early to assist in determining aspects of management, for example, return to school in a paediatric athlete. This will normally be best determined in consultation with a trained neuropsychologist.[56 57]
Baseline NP testing was considered by the panel and was not felt to be required as a mandatory aspect of every assessment; however, it may be helpful to add useful information to the overall interpretation of these tests. It also provides an additional educative opportunity for the physician to discuss the significance of this injury with the athlete. At present, there is insufficient evidence to recommend the widespread routine use of baseline neuropsychological testing.

Concussion Management

The cornerstone of concussion management is physical and cognitive rest until the acute symptoms resolve and then a graded programme of exertion prior to medical clearance and RTP. The current published evidence evaluating the effect of rest following a sports-related concussion is sparse. An initial period of rest in the acute symptomatic period following injury (24–48 h) may be of benefit. Further research to evaluate the long-term outcome of rest, and the optimal amount and type of rest, is needed. In the absence of evidence-based recommendations, a sensible approach involves the gradual return to school and social activities (prior to contact sports) in a manner that does not result in a significant exacerbation of symptoms.
Low-level exercise for those who are slow to recover may be of benefit, although the optimal timing following injury for initiation of this treatment is currently unknown.
As described above, the majority of injuries will recover spontaneously over several days. In these situations, it is expected that an athlete will proceed progressively through a stepwise RTP strategy.[58]

Graduated RTP Protocol

RTP protocol following a concussion follows a stepwise process as outlined in Table 1.
With this stepwise progression, the athlete should continue to proceed to the next level if asymptomatic at the current level. Generally, each step should take 24 h so that an athlete would take approximately 1 week to proceed through the full rehabilitation protocol once they are asymptomatic at rest and with provocative exercise. If any postconcussion symptoms occur while in the stepwise programme, then the patient should drop back to the previous asymptomatic level and try to progress again after a further 24 h period of rest has passed.

Same Day RTP

It was unanimously agreed that no RTP on the day of concussive injury should occur. There are data demonstrating that at the collegiate and high school levels, athletes allowed to RTP on the same day may demonstrate NP deficits postinjury that may not be evident on the sidelines and are more likely to have delayed onset of symptoms.[59–65]

'Difficult' or Persistently Symptomatic Concussion Patient

Persistent symptoms (>10 days) are generally reported in 10–15% of concussions. In general, symptoms are not specific to concussion and it is important to consider other pathologies. Cases of concussion in sport where clinical recovery falls outside the expected window (ie, 10 days) should be managed in a multidisciplinary manner by healthcare providers with experience in sports-related concussion.

Psychological Management and Mental Health Issues

Psychological approaches may have potential application in this injury, particularly with the modifiers listed below.[66 67] Physicians are also encouraged to evaluate the concussed athlete for affective symptoms such as depression and anxiety as these symptoms are common in all forms of traumatic brain injury.[58]

Role of Pharmacological Therapy

Pharmacological therapy in sports concussion may be applied in two distinct situations. The first of these situations is the management of specific and/or prolonged symptoms (eg, sleep disturbance, anxiety, etc). The second situation is where drug therapy is used to modify the underlying pathophysiology of the condition with the aim of shortening the duration of the concussion symptoms.[68] In broad terms, this approach to management should be only considered by clinicians experienced in concussion management.
An important consideration in RTP is that concussed athletes should not only be symptom-free, but also they should not be taking any pharmacological agents/medications that may mask or modify the symptoms of concussion. Where antidepressant therapy may be commenced during the management of a concussion, the decision to RTP while still on such medication must be considered carefully by the treating clinician.

Role of Preparticipation Concussion Evaluation

Recognising the importance of a concussion history, and appreciating the fact that many athletes will not recognise all the concussions they may have suffered in the past, a detailed concussion history is of value.[69–72] Such a history may pre-identify athletes who fit into a high-risk category and provides an opportunity for the healthcare provider to educate the athlete in regard to the significance of concussive injury. A structured concussion history should include specific questions as to previous symptoms of a concussion and length of recovery; not just the perceived number of past concussions. It is also worth noting that dependence on the recall of concussive injuries by teammates or coaches has been demonstrated to be unreliable.[69] The clinical history should also include information about all previous head, face or cervical spine injuries as these may also have clinical relevance. It is worth emphasising that in the setting of maxillofacial and cervical spine injuries, coexistent concussive injuries may be missed unless specifically assessed. Questions pertaining to disproportionate impact versus symptom severity matching may alert the clinician to a progressively increasing vulnerability to injury. As part of the clinical history, it is advised that details regarding protective equipment employed at the time of injury be sought, both for recent and remote injuries.
There is an additional and often unrecognised benefit of the pre-participation physical examination insofar as the evaluation allows for an educative opportunity with the player concerned as well as consideration of modification of playing behaviour if required.

Modifying Factors in Concussion Management

A range of 'modifying' factors may influence the investigation and management of concussion and, in some cases, may predict the potential for prolonged or persistent symptoms. However, in some cases, the evidence for their efficacy is limited. These modifiers would be important to consider in a detailed concussion history and are outlined in Table 2.
Female Gender. The role of female gender as a possible modifier in the management of concussion was discussed at length by the panel. There was no unanimous agreement that the current published research evidence is conclusive enough for this to be included as a modifying factor, although it was accepted that gender may be a risk factor for injury and/or influence injury severity.[73–75]
Significance of LOC. In the overall management of moderate-to-severe traumatic brain injury, duration of LOC is an acknowledged predictor of outcome.[76] Although published findings in concussion describe LOC associated with specific, early cognitive deficits, it has not been noted as a measure of injury severity.[77 78] Consensus discussion determined that prolonged (>1 min duration) LOC would be considered as a factor that may modify management.
Significance of Amnesia and Other Symptoms. There is renewed interest in the role of post-traumatic amnesia and its role as a surrogate measure of injury severity.[64 79 80] Published evidence suggests that the nature, burden and duration of the clinical postconcussive symptoms may be more important than the presence or duration of amnesia alone.[77 81 82] Further, it must be noted that retrograde amnesia varies with the time of measurement postinjury and hence is poorly reflective of injury severity.[83 84]
Motor and Convulsive Phenomena. A variety of immediate motor phenomena (eg, tonic posturing) or convulsive movements may accompany a concussion. Although dramatic, these clinical features are generally benign and require no specific management beyond the standard treatment of the underlying concussive injury.[85 86]
Depression. Mental health issues (such as depression) have been reported as a consequence of all levels of traumatic brain injury including sports-related concussion. Neuroimaging studies using fMRI suggest that a depressed mood following concussion may reflect an underlying pathophysiological abnormality consistent with a limbic-frontal model of depression.[34 87–97] Although such mental health issues may be multifactorial in nature, it is recommended that the treating physician consider these issues in the management of concussed patients.

FPIES: The 'Other' Food Allergy

FPIES: The 'Other' Food Allergy

Anna Nowak-Wegrzyn, Md
Apr 03, 2013
What Is FPIES?
FPIES is a potentially severe, non-immunoglobulin (Ig)E, cell-mediated, gastrointestinal food hypersensitivity typically provoked by cow's milk (CM) or soy. Less commonly, it may result from solid food ingestion, such as rice, oat, fruits, or vegetables. Prevalence in the United States is not known. However, a study from Israel determined that in a large birth cohort of over 13,000 infants, 0.34% developed FPIES to milk in the first year of life, comparable to the 0.5% of infants who developed an IgE-mediated milk allergy.

FPIES: Presentation

FPIES has different manifestations when the food is ingested in a diet on a regular basis vs when it is ingested intermittently or following a period of avoidance. The case presented above included both chronic and acute FPIES caused by CM protein.

What Foods Cause FPIES?

FPIES is commonly caused by CM and soy proteins in formula-fed infants during the first year of life. Delayed introduction of these foods in breastfed infants may result in a later onset. In extremely rare instances, FPIES due to these foods in the mother's breast milk may develop in exclusively breastfed infants, though although only a handful of cases have been reported to date.
FPIES may be induced by solid foods, with a later age at onset than seen with CM- and soy-induced FPIES, a result of the fact that solid foods are introduced later, typically at 4-7 months of age. Rice is the most common FPIES-inducing solid, followed by oats, barley, chicken, turkey, egg white, green pea, peanut, sweet potato, white potato, corn, fruit protein, fish, and mollusks (in adults). The common triggers in FPIES -- rice, oats, and vegetables -- are generally considered to be hypoallergenic and unlikely to cause IgE-mediated food allergy. Thus, they are typically the first solids introduced into an infant's diet.

FPIES to Multiple Foods

In US studies, up to 50% of children with FPIES were found to react to both CM and soy. In contrast, studies from Australia and Israel reported no patients reacting to both of these foods. The differences may be attributed to a more preselected referral population in the US studies and/or delayed introduction of soy formula to the diet of infants reacting to CM.
About one third of infants with CM or soy FPIES develop solid-food FPIES, commonly caused by rice and oat, the grains typically introduced at weaning. The majority of children with solid-food FPIES react to multiple foods. In fact, 80% of infants with solid-food FPIES reacted to more than one food, and 65% were previously diagnosed with CM and/or soy FPIES.[3]

FPIES Diagnosis

Diagnosis of FPIES is not straightforward because the child will not have food-specific IgE antibodies to aid in the diagnosis. If a small child or infant presents with repeated episodes of severe emesis, with or without hypotension upon ingestion of the food, and is well when the implicated food is eliminated from the diet, the diagnosis of FPIES can be established on clinical grounds and an oral food challenge (OFC) is not necessary. However, OFCs are recommended if the child has chronic symptoms despite dietary restrictions and is not thriving in order to both confirm the diagnosis and identify the offending foods. OFCs are also necessary during follow-up to determine when a child has "outgrown FPIES."
An OFC for FPIES is considered a high-risk procedure because of the potential for hypotension. It is usually performed with secure IV access in place prior to the beginning of the challenge. During a food challenge, a serving of food is fed over 45-60 minutes, usually in 3 equal portions, followed by a minimum of 4 hours of observation prior to discharge. A complete blood count is obtained at baseline, before the start of the challenge, and again 4-6 hours later only if symptoms develop, because an elevation in neutrophil count of > 3500/mL is one of the diagnostic criteria for a positive challenge. It should also be repeated prior to discharge if symptoms are absent.