Hospitalisation of adults with Down syndrome: lesson from a 10-year experience from a community hospital.

BACKGROUND: Life expectancy of individuals with Down syndrome (DS) has improved significantly over the past decades. However, there are sparse data documenting the co-morbidities and hospitalisation of adult patients with DS in the literature. The aim of this study was to characterise the co-morbidities and pattern of hospitalisation in adult patients with DS during a 10-year period at the community hospital as well as to compare hospitalisation parameters with the general adult population during the same years. METHOD: We reviewed the medical records of 81 hospitalisations from 37 patients with DS aged 21 to 68 years at Metrowest Medical Center during a 10-year period and compared with those of the general adult population during the same time. Co-morbidities were also described. RESULTS: Adults with DS had a mean age at admission of 48.6 ± 8.8 years with the median length of stay of 3 days (interquartile range 4 days). Male patients were hospitalised longer than female patients (mean 5.0 vs. 2.8 days; P < 0.05), and patients who lived at home were admitted at earlier ages than those who came from residential healthcare facility (mean 41.5 vs. 52.2 years; P < 0.001). The most common cause of hospitalisation was pneumonia/aspiration syndrome (29.6%), and the most common co-morbidity was gastroesophageal reflux disease (GERD)/dysphagia (70.3%). Presence of GERD/dysphagia or seizure disorder was significantly associated with multiple admission and readmission within 1 month (P < 0.05). The mortality rate was 4.9%, and the rate of intensive care unit admission was 8.6%. CONCLUSIONS: Our cohort did not show statistically significant different hospitalisation parameters such as inpatient mortality and average length of stay when compared with general adult population hospitalised at the same years. The care of adult patients with DS presents challenges in internal medicine due to its unique co-morbid profile and signifies the importance of multidisciplinary approach. In order to improve the care of this patient population, their co-morbidities, particularly GERD/dysphagia and seizure disorder, should be optimally managed and comprehensively addressed when patients are hospitalised.

A simulation model for assessing aberration detection methods used in public health surveillance for systems with limited baselines.

Public health officials continue to develop and implement new types of ongoing surveillance systems in an attempt to detect aberrations in surveillance data as early as possible. In public health surveillance, aberrations are traditionally defined as an observed value being greater than an expected historical value for that same time period. To account for seasonality, traditional aberration detection methods use three or more years of baseline data across the same time period to calculate the expected historical value. Due to the recent implementation of short-term bioterrorism surveillance systems, many of the new surveillance systems have limited historical data from which to calculate an expected baseline value. Three limited baseline aberration detection methods, C1-MILD, C2-MEDIUM, and C3-ULTRA, were developed based on a one-sided positive CUSUM (cumulative sum) calculation, a commonly used quality control method used in the manufacturing industry. To evaluate the strengths and weakness of these methods, data were simulated to represent syndromic data collected through the recently developed hospital-based enhanced syndromic surveillance systems. The three methods were applied to the simulated data and estimates of sensitivity, specificity, and false-positive rates for the three methods were obtained. For the six syndromes, sensitivity for the C1-MILD, C2-MEDIUM, and C3-ULTRA models averaged 48.2, 51.3, and 53.7 per cent, respectively. Similarly, the specificities averaged 97.7, 97.8, and 96.1 per cent, respectively. The average false-positive rates for the three models were 31.8, 29.2, and 41.5 per cent, respectively. The results highlight the value and importance of developing and testing new aberration detection methods for public health surveillance data with limited baseline information.

Erythrocyte sedimentation rate and C-reactive protein discrepancy and high prevalence of coronary artery abnormalities in Kawasaki disease.

BACKGROUND: An outbreak of Kawasaki disease (KD) in Colorado between November, 1997, and June, 1998, provided the opportunity to study inflammatory indices and coronary artery abnormalities. METHODS: Medical records of the 33 patients diagnosed with KD at The Children's Hospital during the outbreak were reviewed. Demographic and clinical information, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and echocardiogram results were recorded. Traditional abnormalities (dilatation, aneurysm, ectasia), as well as "prominence" of the coronary arteries were noted. RESULTS: Twenty-five patients had CRP and ESR performed on the day of admission; 11 of 25 (44%) had a discrepancy between the height of the ESR and CRP values (high ESR and low CRP or low ESR and high CRP). The mean CRP was higher in patients who presented in <10 days than in patients who presented in > or =10 days: 13.9 mg/dl vs. 5.2 mg/dl (P = 0.01). The ESR value did not correlate with the day of illness. Age, gender or presence of coronary artery abnormalities did not correlate with the height of CRP or ESR elevation. Thirty percent of patients had at least one abnormality on their initial echocardiogram (dilatation, aneurysm, ectasia). An additional 24% of patients displayed prominence as the only finding on their initial echocardiogram. Of the 33 patients 7 (21.2%) had coronary artery aneurysms. CONCLUSIONS: Many patients with KD have discrepancies in the degree of elevation of CRP and ESR. Physicians should consider obtaining both tests in patients with KD. This outbreak was associated with a high degree of coronary artery abnormalities. The finding of coronary artery prominence is an observation that deserves further study.

Fort Chaffee revisited: the epidemiology of tick-borne rickettsial and ehrlichial diseases at a natural focus.

A retrospective cohort study was conducted among troops training at Fort Chaffee, Arkansas, from May through June 1997, to identify infections caused by tick-borne pathogens. Serum samples were tested by IFAs for antibodies to selected Rickettsia and Ehrlichia species and by an investigational EIA for spotted fever group Rickettsia lipopolysaccharide antigens. Of 1,067 guardsmen tested, 162 (15.2%) had antibodies to one or more pathogens. Of 93 guardsmen with paired serum samples, 33 seroconverted to Rickettsia rickettsii or spotted fever group rickettsiae (SFGR) and five to Ehrlichia species. Most (84.8%) of the personnel who seroconverted to SFGR were detected only by EIA, and seropositivity was significantly associated with an illness compatible with a tick-borne disease. In addition, 34 (27%) of 126 subjects with detectable antibody titers reported a compatible illness. The primary risk factor for confirmed or probable disease was finding > 10 ticks on the body. Doxycycline use and rolling up of long sleeves were protective against seropositivity. The risk of transmission of tick-borne pathogens at Fort Chaffee remains high, and use of the broadly reactive EIA suggests that previous investigations may have underestimated the risk for infection by SFGR. Measures to prevent tick bite and associated disease may require reevaluation.

Rocky Mountain spotted fever in the United States, 1993-1996.

During 1993 through 1996, 2,313 cases of Rocky Mountain spotted fever (RMSF) were reported to the Centers for Disease Control and Prevention (CDC) by 42 states and the District of Columbia through the National Electronic Telecommunications System for Surveillance (NETSS). During this same interval, 1,752 case report forms (CRFs) were submitted to CDC and 1,253 (70%) of the cases were categorized as confirmed RMSF by laboratory testing. On the basis of analyses performed with NETSS data, the average annual RMSF incidence during 1993-1996 was 2.2 cases per million persons; the incidence rose from 1.8 in 1993 to 3.3 per million persons in 1996. Incidence for confirmed cases was highest among children 5-9 years of age (3.7 per million) and lowest among individuals older than 70 years of age (1.4 per million). The south Atlantic region accounted for the largest proportion of confirmed cases (52%). The case-fatality rate was highest among persons 70 years of age and older (9.0%) and lowest among adults 40-49 years of age (0.6%).

An investigation into the possibility of transmission of tick-borne pathogens via blood transfusion. Transfusion-Associated Tick-Borne Illness Task Force.

BACKGROUND: Tick-borne illnesses were diagnosed in a group of National Guard members, including some who had donated blood a few days before the onset of symptoms. A voluntary recall of those blood components was issued and a multistate investigation was conducted to determine if transfusion-transmitted illness had occurred. STUDY DESIGN AND METHODS: Donors and recipients were asked to complete questionnaires regarding symptoms and risk factors for infection and to provide blood samples for laboratory analysis. RESULTS: Among National Guard personnel who donated blood, 12 individuals were found to have a confirmed or probable case of Rocky Mountain spotted fever or ehrlichiosis. A total of 320 units (platelets or packed red cells) from 377 donors were transfused into 129 recipients. Although 10 recipients received units from National Guard personnel with confirmed or probable infection, none became ill. CONCLUSION: Transfusion-transmitted illness did not occur. Despite the awareness of the risk for tick-borne diseases and the use of tick-preventive measures, many National Guard personnel reported exposure to ticks. In addition to augmenting current tick-preventive measures, scheduling blood drives before rather than after field exercises could further reduce the potential for transmission of tick-borne pathogens.

Hidden mortality attributable to Rocky Mountain spotted fever: immunohistochemical detection of fatal, serologically unconfirmed disease.

Rocky Mountain spotted fever (RMSF) is the most severe tickborne infection in the United States and is a nationally notifiable disease. Since 1981, the annual case-fatality ratio for RMSF has been determined from laboratory-confirmed cases reported to the Centers for Disease Control and Prevention (CDC). Herein, a description is given of patients with fatal, serologically unconfirmed RMSF for whom a diagnosis of RMSF was established by immunohistochemical (IHC) staining of tissues obtained at autopsy. During 1996-1997, acute-phase serum and tissue samples from patients with fatal disease compatible with RMSF were tested at the CDC. As determined by indirect immunofluorescence assay, no patient serum demonstrated IgG or IgM antibodies reactive with Rickettsia rickettsii at a diagnostic titer (i.e., >/=64); however, IHC staining confirmed diagnosis of RMSF in all patients. Polymerase chain reaction validated the IHC findings for 2 patients for whom appropriate samples were available for testing. These findings suggest that dependence on serologic assays and limited use of IHC staining for confirmation of fatal RMSF results in underestimates of mortality and of case-fatality ratios for this disease.

Immunogenicity of two recombinant hepatitis B vaccines in older individuals.

PURPOSE: Currently available hepatitis B vaccines are recombinant, yeast-derived preparations given in 10-micrograms or 20-micrograms doses. The optimum dose remains controversial. We sought to assess the relative immunogenicity of two hepatitis B vaccines, given in different doses, in older individuals. PATIENTS AND METHODS: In a multicenter, double-blind, randomized clinical trial, a total of 460 healthy subjects between 39 and 70 years of age were screened and immunized with either Engerix-B 20 micrograms or Recombivax HB 10 micrograms in standard, intramuscular, 3-dose regimens. Of these, 397 subjects were eligible to continue vaccination. Immunogenicity was measured by determination of antibody to hepatitis B surface antigen (anti-HBs). Seroconversion and seroprotection rates, and geometric mean titers of anti-HBs were calculated at 1, 3, 6, and 8 months after the initial dose of vaccine. RESULTS: Seroprotection rates for subjects receiving the 20-micrograms dose of vaccine were slightly, but not significantly, greater than for subjects receiving the 10-micrograms dose, at each time point. However, at 3 months, males receiving the higher dose had significantly higher seroprotection rates than males receiving the lower dose: 63% versus 37% (p < 0.001). At 8 months, geometric mean titers for the group receiving Engerix-B 20 micrograms were significantly greater than that for the group receiving Recombivax HB 10 micrograms: 840 mIU/mL versus 340 mIU/mL (p = 0.001). CONCLUSIONS: Immunization with the 20-micrograms dose of recombinant hepatitis B virus vaccine appeared to result in more rapid development of seroprotective anti-HBs titers in older men and in higher titers of anti-HBs at the completion of vaccination when compared to the 10-micrograms dose. The latter data suggest that the 20-micrograms dose may result in a longer duration of seroprotective anti-HBs titers.

Mediterranean spotted fever in children returning from France.

Although the incidence of Mediterranean spotted fever has increased dramatically in parts of Europe, Africa, and Asia, the disease is only rarely seen in travelers. We describe two children who had traveled in southern France and subsequently had rash and lymphadenopathy develop. Both children were treated with doxycycline and had unequivocal serologic evidence of Mediterranean spotted fever develop. Although this disease is usually mild, in the absence of a tick bite the disease can easily be confused with other febrile exanthems. We describe these patients to reemphasize the influence that international travel has brought to pediatrics.

Randomized clinical trial of aztreonam and aminoglycoside antibiotics in the treatment of serious infections caused by gram-negative bacilli.

Aztreonam was compared with aminoglycoside antibiotics (tobramycin and amikacin) in a randomized, prospective, clinical trial in serious infections caused by gram-negative bacilli (GNB). A total of 43 evaluable patients with 47 infected sites were treated with aztreonam, and 41 evaluable patients were treated with aminoglycosides for 43 infections. Of patients treated with aztreonam, 17 were bacteremic, as were 12 of those treated with aminoglycosides. Clinical and microbiologic response rates were similar, except that only 5 of 11 patients with pneumonia were considered to be clinically cured with aminoglycoside therapy, while 5 of 6 patients with pneumonia treated with aztreonam were cured. Renal impairment was observed in 9 of 54 patients who received aminoglycoside antibiotics, but in only 2 of 53 patients treated with aztreonam. Hearing impairment developed in one patient treated with tobramycin. Transient elevations of serum transaminase levels occurred in 9 of 53 patients treated with aztreonam and in only 2 of 54 aminoglycoside-treated patients. Diarrhea and superinfection occurred with equal frequency in both groups. Serum concentrations of bactericidal activity could not be correlated with the outcome of therapy. Aztreonam appears to have comparable clinical efficacy with aminoglycoside antibiotics for the treatment of serious infections caused by aerobic and facultative GNB. Its use as a single agent for the treatment of serious lower respiratory infections caused by GNB warrants further evaluation.

Treatment of pancreatitis. When do antibiotics have a role?

Experimental and clinical data on the use of antibiotics in treatment of pancreatitis vary widely, depending on the cause of the disease. Antibiotics have little effect on alcoholic or idiopathic pancreatitis, but they play a major role in treatment of bacterial infections in gallstone pancreatitis. Some antibiotics are effective in necrotizing pancreatitis; however, surgery and extensive debridement are often necessary when abscess is present or multiple-organ failure occurs.

Faculty training seminars in family systems.

Family physician faculty members were instructed in the concepts and applications of family systems theory as part of a structured faculty development series. An experiential component in the seminars allowed faculty members to present their own three generational genogram. Evaluations revealed the unexpected outcome of increased understanding of faculty colleagues in the work setting.

Xanthogranulomatous pyelonephritis caused by methicillin-resistant Staphylococcus aureus.

Localized xanthogranulomatous pyelonephritis due to methicillin-resistant Staphylococcus aureus developed in a 41-year-old diabetic patient. She had recurrent bacteremia despite appropriate therapy with vancomycin. Nephrectomy was required for cure and clinical diagnosis. This report emphasizes differences in the clinical presentation and pathogenesis of xanthogranulomatous pyelonephritis caused by S. aureus. Compared with the common form of xanthogranulomatous pyelonephritis caused by gram-negative bacilli, the localized disease due to S. aureus probably results from hematogenous seeding and is not associated with nephrolithiasis or ureteral obstruction. Furthermore, this report indicates that xanthogranulomatous pyelonephritis may be caused by methicillin-resistant S. aureus, a rapidly emerging nosocomial pathogen.

Pseudobacteremia traced to cross-contamination by an automated blood culture analyzer.

Twenty-three episodes of pseudobacteremia occurring over a seven-month period were traced to cross-contamination by the automated blood culture analyzer (BACTEC 460) used in the microbiology laboratory. An epidemiologic investigation of an unusual cluster of three patients with pseudobacteremia caused by oxacillin-resistant Staphylococcus aureus led to the identification of the problem. Mock trials of the blood culture procedure confirmed that the blood culture analyzer was the source of contamination. After the needle sterilizer was replaced by the manufacturer, the problem of cross-contamination abated. Contamination of sterile blood cultures by an instrument intended to identify bacteremia rapidly may lead to incorrect diagnosis, unnecessary administration of antibiotics and prolonged hospitalization. Because of the widespread use of automated blood culture analyzers in the US, physicians, microbiologists, and infection control personnel should be alert to the possibility of cross-contamination and the subtle way in which it may present.