Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005-2011.

OBJECTIVES: It is currently unknown whether chronic wasting disease (CWD), a transmissible spongiform encephalopathy of cervids, is transmissible to humans. Reported on here are the behavioural risk factors and health conditions associated with a six-year follow-up of a known point-source exposure to a CWD infected deer in an Upstate New York community. STUDY DESIGN: Longitudinal. METHODS: The Oneida County Chronic Wasting Disease Surveillance Project was launched in 2005 in response to a point-source exposure to a CWD infected deer at a March 2005 Sportsmen's feast in Upstate New York. Eighty-one exposed individuals participated in the 2005 baseline data collection, and were sent follow-up questionnaires following each deer hunting season between 2005 and 2011. RESULTS: Over a six year period, participants reported a reduction in overall venison consumption. Participants reported no significant changes in health conditions, although several conditions (vision loss, heart disease, type 2 diabetes, weight changes, hypertension, and arthritis), were significantly associated with age. CONCLUSIONS: To this day, this incident remains the only known large-scale point-source exposure to a CWD infected deer. Prion diseases can incubate for multiple decades before the manifestation of clinical symptoms; thus, continued surveillance of this exposed study population represents a unique opportunity to assess the risk of CWD transmission to humans. This project is uniquely situated to provide the first epidemiological evidence of CWD transmission to humans, should it occur.

Early estimation of myocardial damage in conscious dogs and patients with evolving acute myocardial infarction.

To estimate the ultimate extent of myocardial damage during evolving myocardial infarction in conscious dogs and patients, we analyzed early serum creatine phosphokinase (CPK) changes with nonlinear curve-fitting techniques. In experiments with dogs, serial serum CPK changes were fit to a log-normal function by the least squares method; the extent of the completed infarct was calculated by analysis of observed serum CPK changes and verified by measurement of myocardial CPK depletion 24 h after coronary occlusion. Early prediction of myocardial damage was based on projected serum CPK values from best fit curves based on data obtained during the first 5 h after initial elevation of enzyme activity. The correlation between predicted and observed values was close (r > 0.96, n = 11). In 11 additional conscious animals subjected to coronary occlusion, isoproterenol was administered continuously as soon as damage had been estimated from projected serum CPK values. The extent of the completed infarct was assessed by analysis of all serial serum CPK values and verified by analysis of myocardial CPK depletion 24 h after coronary occlusion. In each experiment the calculated completed infarct size exceeded infarct size projected before administration of isoproterenol (average increase = 44+/-10 [SE]%). When similar calculations were applied in experiments with eight dogs treated with propranolol, myocardial salvage was detected in 50% of the animals. In 30 patients with uncomplicated acute myocardial infarction the extent of the completed infarct, measured by analysis of CPK activity in serum samples obtained every 2 h, was compared with damage estimated from CPK values projected by the best fit log-normal curve derived from data obtained during the first 7 h after the initial serum CPK elevation. The estimate of damage based on early data correlated closely with the extent of infarction calculated from all available serial serum CPK values (r = 0.93, n = 30). Thus, the extent of the completed infarct could be estimated accurately during the early evolution of infarction. In patients with spontaneous extension of infarction manifested by chest pain and electrocardiographic changes, the calculated extent of the completed infarct exceeded that predicted. Conversely, salvage of myocardium, after reduction of myocardial oxygen requirements by administration of trimethaphan, was reflected by reduction of the extent of the calculated completed infarct with respect to that predicted from early serum CPK changes.

Somatic mutation and CDR3 lengths of immunoglobulin kappa light chains expressed in patients with rheumatoid arthritis and in normal individuals.

Immunoglobulin secretion by plasma cells infiltrating synovial membranes is a prominent feature of RA. Previous analyses of a cDNA library generated from synovium of RA patient BC revealed immunoglobulin kappa light chain transcripts with extensive somatic mutation, frequent N region addition, and unexpected variation in the lengths of CDR3 regions which form the center of the antigen binding site. To determine if these characteristics are present in other individuals, we performed reverse transcription-polymerase chain reaction amplification and sequenced > or = 10 V kappa-containing amplicons from nine tissue samples: synovia of three individuals with long-standing RA (including patient BC), PBLs of two of these individuals, and PBLs or splenocytes of four normal individuals. Increased levels of somatic mutation in PBLs appeared to correlate with increased age, which may reflect accumulation of circulating memory cells and/or decreased bone marrow production of naive B lymphocytes. Two of three RA synovial samples and both RA PBL samples exhibited increased proportions of clones with unusual CDR3 lengths. Enrichment for these antibody binding sites could be due to abnormal regulation of the emerging repertoire or to selection for B lymphocytes bearing antibodies of unusual specificity, and may play a role in the pathogenesis of RA.

Congruence of diagnoses 2 years after a first-admission diagnosis of psychosis.

BACKGROUND: Diagnostic changes may reflect evolution of an illness, emergence of newly disclosed information, or unreliability of assessment. This study evaluates the stability of research diagnoses in a heterogeneous first-admission sample with psychosis. METHODS: A group of 547 subjects initially diagnosed with a psychosis were reassessed 6 and 24 months after enrollment. The DSM-IV consensus diagnoses were formulated by psychiatrists blind to previous research diagnoses. The analysis focuses on agreement over time and the effects of demographic, family history, and clinical variables on the shift from a nonschizophrenia diagnosis to schizophrenia. RESULTS: Seventy-two percent of 6- and 24-month diagnoses were congruent. The most temporally consistent 6-month categories were schizophrenia (92%), bipolar disorder (83%), and major depression (74%); the least stable were psychosis not otherwise specified (44%), schizoaffective disorder (36%), and brief psychosis (27%). The most frequent shift in diagnosis at 24 months was to schizophrenia spectrum (n=45). These 45 subjects had a similar illness course after 6 months as the 171 subjects in this category at both assessments, but their prior clinical functioning was better. Risk factors predicting change to a schizophrenia spectrum diagnosis include facility variables (schizophrenia diagnosis, longer stays, and given antipsychotic medication on hospital discharge); prehospital features (psychotic > or =3 months before admission, poorer adolescent adjustment, lifetime substance disorder); and negative symptoms. CONCLUSIONS: Changes in diagnosis, particularly to schizophrenia, are mostly attributable to the evolution of the illness. Rigid adherence to DSM-IV requirements may have led to underdiagnosis of schizophrenia. The findings support the need for a longitudinally based diagnostic process in incidence samples.

Displacement of the common peroneal nerve in posterolateral corner injuries of the knee.

We reviewed the relationship between the pattern of damage to the posterolateral corner of the knee and the position of the common peroneal nerve in 54 consecutive patients with posterolateral corner disruption requiring surgery. We found that 16 of the 18 patients with biceps avulsions or avulsion-fracture of the fibular head had a displaced common peroneal nerve. The nerve was pulled anteriorly with the biceps tendon. None of the 34 proximal injuries resulted in an abnormal nerve position. Whenever bone or soft-tissue avulsion from the fibular head is suspected, the surgeon should expect an abnormal position of the common peroneal nerve and appreciate the increased risk of iatrogenic damage.

Making strides towards better mental health care in Peru: Results from a primary care mental health training.

Our program attempted to improve attitudes and confidence of Peruvian primary care physicians (PCPs) providing mental health care. The training program underwent an evaluation to determine impact of sustained confidence in performing medical and psychiatric procedures, and application of learned skills. Fifty-two Peruvian primary care practitioners were trained at the Harvard Program in Refugee Trauma (HPRT) over a two-week period. There was significant improvement in PCPs' confidence levels of performing psychiatric procedures (counseling, prescribing medications, psychiatric diagnosis, assessing the risk for violence, and treating trauma victims) when comparing baseline and post-two-week to one year follow-up. When comparing post-two-week and one-year follow-up quantitative measures, confidences levels went slightly down. This may be an implication that the frequency of trainings and supervisions are needed more frequently. In contrast, qualitative responses from the one-year follow-up revealed increase in victims of violence clinical care, advocacy, awareness, education, training, policy changes, accessibility of care, and sustainment of diagnostic tools. This study supports the feasibility of training PCP's in a culturally effective manner with sustainability over time.

The psychosocial impact of war trauma and torture on Southeast Asian refugees.

More than 700,000 refugees from Southeast Asia have settled in the United States since 1975. Although many have suffered serious trauma, including torture, few clinical reports have described their trauma-related symptoms and psychosocial problems. The authors conducted a treatment study of 52 patients in a clinic for Indochinese. They found that these patients were a highly traumatized group; each had experienced a mean of 10 traumatic events and two torture experiences. Many of the patients had concurrent diagnoses of major affective disorder and posttraumatic stress disorder as well as medical and social disabilities associated with their history of trauma. The authors also found that Cambodian women without spouses demonstrated more serious psychiatric and social impairments than all other Indochinese patient groups.

Indochinese versions of the Hopkins Symptom Checklist-25: a screening instrument for the psychiatric care of refugees.

The United States is accepting the largest number of displaced persons since World War II. Over 70% are Southeast Asians; many have suffered serious war trauma and torture. Cultural differences in health-seeking behavior and lack of specialized mental health services make the recognition of psychiatric distress in Southeast Asia refugees difficult for American health care providers. The authors describe the development and validation of Cambodian, Laotian, and Vietnamese versions of the Hopkins Symptom Checklist-25. This brief, simple, and reliable instrument is well received by refugee patients, offers an effective screening method for the psychiatric symptoms of anxiety and depression, and is especially helpful for evaluating trauma victims.

HIV infection among young adults with psychotic disorders.

OBJECTIVE: The authors examined HIV infection among young adults with newly diagnosed psychotic disorders. METHODS: The study was based on a research cohort of 320 first-admission patients aged 20-39 years in a semirural-suburban county. Research assessments and medical records were systematically reviewed for information about HIV status. RESULTS: Despite the fact that few patients were tested for HIV, 12 (3.8%) of the 320 patients had a known HIV infection. In all 12 cases, the HIV infection was contracted before the onset of psychosis. AIDS was the leading cause of mortality in the 320 patients. CONCLUSIONS: The HIV epidemic may be having an important effect on the etiology and the course of psychotic disorders.

Assessing symptom change in Southeast Asian refugee survivors of mass violence and torture.

The authors evaluated changes in symptoms and levels of perceived distress of 21 Cambodian, 13 Hmong/Laotian, and 18 Vietnamese patients before and after a 6-month treatment period. Most of the patients improved significantly. Cambodians had the greatest and Hmong/Laotians had the least reductions in depressive symptoms. Although psychological symptoms improved, many somatic symptoms worsened. The authors conclude that refugee survivors of multiple traumata and torture can be aided by psychiatric care. They recommend investigations with larger samples and suitable control groups to further clarify the relative contributions of trauma, diagnosis, and acculturation stress to treatment outcome.

Relationship between type of insurance and care during the early course of psychosis.

OBJECTIVE: Little is known about the relationship between insurance and care in the early course of psychosis. This study explored the insurance status of first-admission psychotic patients and the relationship between type of insurance and care received up to this admission. METHOD: Data are from the Suffolk County Mental Health Project, an epidemiologic study of first-admission psychosis. Data on insurance status (N=525) were pooled from hospital records, respondents, and significant others. Logistic regression analysis, controlling for key background variables and diagnosis, was used to study the relationship between insurance and care. RESULTS: At first admission, 233 (44%) of the patients had no insurance, 78 (15%) had Medicaid or Medicare, 203 (39%) had private insurance, eight (1.5%) were insured by the Veterans Administration, and the insurance status of three (1.5%) was unknown. Having private insurance increased the likelihood of having received previous mental health treatment (psychotherapy specifically), being admitted voluntarily, being hospitalized in a community hospital rather than a public hospital, and being hospitalized within 3 months of onset of psychosis. Having Medicaid/Medicare increased the likelihood of receiving nonantipsychotic medication before this hospitalization, admission to a community hospital rather than a public hospital, having received previous mental health treatment in general, and voluntary admission. CONCLUSIONS: During the early course of psychotic illness, many people lack any type of health insurance, and this is associated with a decreased likelihood of obtaining care before their first hospital admission.

Is there an association between duration of untreated psychosis and 24-month clinical outcome in a first-admission series?

OBJECTIVE: The authors examined the duration of untreated psychosis, defined as the interval from first psychotic symptom to first psychiatric hospitalization, in a county-wide sample of first-admission inpatients who had received no previous antipsychotic medication. Differences between diagnostic groups in 24-month illness course and clinical outcomes as well as relationships between outcomes and duration of untreated psychosis were evaluated. METHOD: The data were derived from subjects in the Suffolk County Psychosis Project who were diagnosed at 24-month follow-up according to DSM-IV as having schizophrenia or schizoaffective disorder (N=155), bipolar disorder with psychotic features (N=119), or major depressive disorder with psychotic features (N=75). Duration of untreated psychosis was derived from the Structured Clinical Interview for DSM-III-R, medical records, and information from significant others. Measures at 24-month follow-up included consensus ratings of illness course, Global Assessment of Functioning Scale scores for the worst week in the month before interview, and current affective and psychotic symptoms. RESULTS: The median duration of untreated psychosis was 98 days for schizophrenia, 9 days for psychotic bipolar disorder, and 22 days for psychotic depression. Duration of untreated psychosis was not significantly associated with 24-month illness course or clinical outcomes in any of the diagnostic subgroups. CONCLUSIONS: Although these findings require replication in other epidemiologically based first-admission samples, at face value they do not support the suggestion of a psychotoxic effect of prolonged exposure to untreated psychosis.

Homelessness among individuals with psychotic disorders hospitalized for the first time: findings from the Suffolk County Mental Health Project.

OBJECTIVE: Although data suggest that homelessness among persons with severe mental disorders is both distressing and common, several important epidemiologic questions remain unanswered. This study reports on the occurrence of homelessness in a quasi-representative sample of persons newly hospitalized with psychotic disorders. The authors also compared rates of homelessness in different diagnostic groups and among groups with differing symptom profiles. METHOD: The study was based on data from 237 first-admission patients hospitalized at 10 of the 12 inpatient facilities in eastern Long Island, N.Y. Consensus diagnoses were derived from multiple sources of information, including the Structured Clinical Interview for DSM-III-R. Patients were followed over a 24-month period after initial interview. Homelessness histories were based on subject self-reports. RESULTS: Fifteen percent of the patients had experienced at least one episode of homelessness before or within 24 months of their first psychiatric hospitalization. In more than two-thirds of these cases, the initial homeless episode had occurred before the first hospitalization. There were no significant differences in the risk of homelessness among diagnostic groups. Among subjects diagnosed with schizophrenia and related disorders, those with high levels of negative symptoms had a significantly greater risk of prehospitalization homelessness than those with low symptom levels. CONCLUSIONS: The high rate of homelessness observed must be viewed with profound concern by clinicians, consumers, and policymakers alike. The findings support the importance of intervening early in the course of disorder, particularly for persons diagnosed with psychotic illnesses.

Aerosol pentamidine prophylaxis following Pneumocystis carinii pneumonia in AIDS patients: results of a blinded dose-comparison study using an ultrasonic nebulizer.

PURPOSE: To compare the efficacy and safety of three different doses of prophylactic aerosol pentamidine in patients with one prior episode of Pneumocystis carinii pneumonia (PCP) and the acquired immunodeficiency syndrome. PATIENTS AND METHODS: The design of the study was a double-blind, randomized, dose-comparison clinical trial conducted at 13 medical centers within the United States. In stage I of the trial, patients were randomized to receive either 5 mg, 60 mg, or 120 mg of aerosol pentamidine delivered biweekly with the Fisoneb (Fisons, Inc., Rochester, New York) ultrasonic nebulizer. After 24 weeks of therapy, patients entered stage II of the trial, where the 5-mg group was re-randomized to either the 60-mg or 120-mg group. RESULTS: One hundred seventy-five patients entered stage I of the trial and received prophylaxis for a mean of 123.6 days. Seven assigned to the 5-mg biweekly dosing schedule had a confirmed recurrence of PCP, compared with none in the 60-mg group (p = 0.007) and three in the 120-mg group (p = 0.304). During stage II of the trial, eight patients in the 60-mg group and one additional patient in the 120-mg group had recurrent PCP. After 52 weeks of observation, the likelihood of being PCP-free was 88.0% in the 60-mg group and 93% in the 120-mg group (p = 0.712). Minor adverse events related to aerosol pentamidine administration included cough, taste perversion, chest pain, bronchospasm, and dyspnea. These side effects were more common in the 60-mg and 120-mg treatment groups and resulted in withdrawal from the study by one patient. Serious events were more common after 24 weeks of therapy and included asymptomatic hypoglycemia (five), pancreatitis (two), pneumothorax (one), and extrapulmonary pneumocystosis (one). CONCLUSIONS: These results demonstrate that biweekly administration of 60 mg or 120 mg of aerosol pentamidine significantly decreases PCP recurrence when compared with a 5-mg regimen or findings in historic controls and is generally well tolerated. There is no significant difference in effect or safety between these two dosing regimens in patients followed for at least 52 weeks of therapy.

Forensic evidence findings in prepubertal victims of sexual assault.

OBJECTIVE: The American Academy of Pediatrics recommends forensic evidence collection when sexual abuse has occurred within 72 hours, or when there is bleeding or acute injury. It is not known whether these recommendations are appropriate for prepubertal children, because few data exist regarding the utility of forensic evidence collection in cases of child sexual assault. This study describes the epidemiology of forensic evidence findings in prepubertal victims of sexual assault. METHODS: The medical records of 273 children <10 years old who were evaluated in hospital emergency departments in Philadelphia, Pennsylvania, and had forensic evidence processed by the Philadelphia Police Criminalistics Laboratory were retrospectively reviewed for history, physical examination findings, forensic evidence collection, and forensic results. RESULTS: Some form of forensic evidence was identified in 24.9% of children, all of whom were examined within 44 hours of their assault. Over 90% of children with positive forensic evidence findings were seen within 24 hours of their assault. The majority of forensic evidence (64%) was found on clothing and linens, yet only 35% of children had clothing collected for analysis. After 24 hours, all evidence, with the exception of 1 pubic hair, was recovered from clothing or linens. No swabs taken from the child's body were positive for blood after 13 hours or sperm/semen after 9 hours. A minority of children (23%) had genital injuries. Genital injury and a history of ejaculation provided by the child were associated with an increased likelihood of identifying forensic evidence, but several children had forensic evidence found that was unanticipated by the child's history. CONCLUSIONS: The general guidelines for forensic evidence collection in cases of acute sexual assault are not well-suited for prepubertal victims. The decision to collect evidence is best made by the timing of the examination. Swabbing the child's body for evidence is unnecessary after 24 hours. Clothing and linens yield the majority of evidence and should be pursued vigorously for analysis.

Late angiographic follow-up after successful coronary arterial thrombolysis and angioplasty during acute myocardial infarction.

Emergency percutaneous transluminal coronary angioplasty (PTCA) is accepted as an important reperfusion intervention for acute myocardial infarction (AMI). Although its primary success rate is well documented, the frequency of restenosis after this procedure is unclear. The frequency of restenosis was determined in patients undergoing emergency PTCA at least 6 months after PTCA was performed during AMI. Of 66 consecutive patients undergoing emergency PTCA, 25 had a second, elective catheterization at an average of 22 months after AMI and 6 underwent repeat catheterization because of recurrent chest pain. Restenosis of the PTCA site was found in 10 of the 31 patients (32%) restudied. Also, 14 (45%) of these 31 patients showed progression of narrowing in the non-infarct-related coronary arteries. In summary, patients in whom AMI is treated by PTCA are at risk for restenosis and for progressive narrowing of the non-infarct artery.

A randomized trial of interferon alpha therapy for HIV type 1 infection.

The immunologic and virologic efficacy and safety of interferon a (IFN-alpha) administered in combination with zidovudine (ZDV) and zalcitabine (ddC) was evaluated in HIV-infected subjects with CD4+ cell counts between 300 and 500 cells/ml and no more than 14 weeks of prior antiretroviral therapy. A total of 256 subjects enrolled in an open-label, randomized controlled trial. Subjects were randomized equally into treatment groups. All subjects received ZDV and ddC, while half also receive IFN-alpha (3 MU subcutaneously every 24 hr). At 48 weeks the median average area under the curve minus baseline (AAUCMB) for plasma HIV-1 RNA for the two-drug group was -0.68 versus -0.75 log10 copies/ml for the IFN-alpha group (p = 0.046). Mean HIV-1 RNA changes from baseline to 48 weeks for these groups were -0.65 and -1.12 log10 copies/ml, respectively (p = 0.010). The median AAUCMB for CD4+ cell count for the two-drug group was 28 versus -1 cells/mm3 for the IFN-alpha group (p = 0.011). Neutropenia, anemia, and drug intolerance were more common in the IFN-alpha group. This study demonstrates that IFN-alpha inhibits HIV-1 replication but attenuates the CD4+ cell response to dual therapy with ZDV and ddC.

Mechanisms of toxicity/carcinogenicity and Superfund decisions.

Heavy metals that contaminate soils and water usually exist in various oxidation states and form a number of compounds with different physical and chemical characteristics. These differences are often reflected in dramatic variation in toxicokinetic and biologic properties. Such variation in properties, critical in determining intrinsic toxicity, often causes a great deal of uncertainty in analyses of public health risks at sites where metal exposure is evaluated. In the Superfund program, such uncertainties may substantially undermine attempts to characterize potential impacts to populations exposed to metals from improperly disposed waste. In the case of chromium, risk assessment uncertainties can be considerable and fall generally into two categories. First, there is almost no information on potential health effects due to chronic oral exposure to chromium-containing compounds, and a nonquantifiable and probably large uncertainty exists in establishing no-effect levels. In fact, reference doses (RfDs) for CrIII and CrVI are based on chronic studies in which no adverse effects were seen even at the highest dose. Considerations of bioavailability, deduced from site characterization data, and acute toxicity indicate that general application of these RfDs may lead to highly inaccurate estimations of risk. Second, because of the ready reduction of CrVI in biological systems, it has not been possible to separate effects of CrVI from those of CrIII. Thus, data on the relative toxicity and carcinogenicity of these two species is sparse and difficult to interpret. Moreover, kinetic considerations make it difficult to determine the site and rates of reduction of CrVI. This makes prediction of target site concentrations of the two species difficult.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential lobe lavage for diagnosis of acute Pneumocystis carinii pneumonia in patients receiving prophylactic aerosolized pentamidine therapy.

The diagnostic yield of bronchoalveolar lavage (BAL) for Pneumocystis carinii pneumonia (PCP) in patients infected with human immunodeficiency virus has been reported to be 95 percent, but falls to 62 percent in patients receiving aerosolized pentamidine. Because aerosolized pentamidine appears to be preferentially deposited in the middle and lower lobes, we postulated that an upper lobe lavage would have a higher diagnostic yield than the standard middle/lower lobe lavage in patients receiving aerosolized pentamidine. Twenty-five patients receiving aerosolized pentamidine suspected of having acute PCP underwent separate BAL of an upper lobe and lower lobe as well as transbronchial biopsy. Fifteen of the 25 (60 percent) were diagnosed as having PCP. Of the 15, one had the samples inadvertently combined. In the remaining 14, BAL was positive for P carinii organisms in 12 lavages of the lower lobe and 14 of the upper lobe. Upper lobe lavage had statistically significantly more P carinii organisms by semiquantitative technique than the lower lobe. In patients receiving aerosolized pentamidine, who develop acute PCP, an upper lobe lavage may have a higher diagnostic yield than the standard middle/lower lobe lavage. In addition, the transbronchial biopsy specimen offered no treatable diagnosis that was not made by lavage alone in the 25 patients. This raises the question of the utility of transbronchial biopsies in these patients.

Evaluation of head injury in a pediatric emergency department: pretrauma and posttrauma system.

OBJECTIVE: To determine if trauma center protocols affect the number of tests and consultations performed and the length of time spent in the emergency department or hospital. DESIGN: A retrospective review and comparison of treatment for children with isolated head injury admitted to the emergency department before trauma center designation (group 1, 1985), and 5 years after implementation of trauma center protocols (group 2, 1991). SETTING: Urban children's hospital, level I trauma center. RESULTS: One hundred sixty-five children met the enrollment criteria in 1985 and 162 met the criteria in 1991. Falls were the predominant mechanism of injury (55%) for both years. For patients with moderate injury (Glasgow Coma Scale score, 9-12) or severe injury (Glasgow Coma Scale score, <9), there was no difference in radiographic or laboratory evaluation. For patients with minimal head injury (Glasgow Coma Scale score, 15, no loss of consciousness, amnesia, seizure, focal neurologic findings, or persistent symptoms) and minor head injury (Glasgow Coma Scale score, >12, and loss of consciousness or amnesia), more radiologic and laboratory studies were done in 1991 that showed no clinically significant abnormalities. Patients with minimal head injury in group 2 were 14 times more likely to have cranial computed tomographic scans performed (95% confidence interval [CI], 3.4-67); 11 times more likely to have cervical spine radiographs (95% CI, 2.2-76.6); and 23 times more likely to have hepatic enzymes obtained (95% CI, 3-491). These differences persisted when analyzed by both the age of the patient and mechanism of injury. CONCLUSIONS: Application of trauma system protocols to isolated head injury patient evaluation results in increased use of laboratory and radiologic services. These practices have the potential to increase the cost of medical care without significantly improving outcome.