Michelle's Story: The Complexity of Patient Care in a Family Medicine Residency Clinic.

Family medicine covers all ages and specializes in chronic disease management as well as acute care medicine. As the health of the population continues to grow in complexity, treating patients appropriately and efficiently is imperative to improving health outcomes and managing health care costs. Family medicine physicians are uniquely poised to provide this type of care. A patient story plus a look at the patients seen over the course of a day within a family medicine residency clinic explores the complexity of care and the ability of family medicine physicians to provide the necessary care. Taking a close look at who comes through our door on a particular day highlights 3 points: primary care physicians are seeing patients with an increasing complexity of needs, our society is witnessing an extreme increase in patients suffering with mental health problems and substance use disorders, and addressing social determinants of health must be part of the solution.

Cow milk does not affect adiposity in growing piglets as a model for children.

The effect of milk consumption on childhood obesity is unclear and a direct demonstration of an association is needed. In the present study, we used piglets as a model for prepubertal children to determine the effect of milk on adipose tissue. Two studies were conducted: study 1 with 5-wk-old male piglets (n = 8) and study 2 with 8- to 9-wk-old male piglets (n = 12). The piglets were fed a normal growing diet and randomly assigned to receive daily either 750 mL of whole cow milk or an isocaloric maltodextrin solution (control). For approximately 12 wk, body weight, feed intake, and subcutaneous back fat thickness were determined ultrasonographically and recorded. At euthanasia, back and neck fat thicknesses were measured and samples of back fat were collected for adipose histology. In study 1, but not study 2, piglets receiving milk grew more and ate more compared with control. In study 1, both back fat and neck fat thickness were greater in the milk-fed piglets and they had a higher frequency of small adipocytes and a lower frequency of intermediate and large adipocytes compared with controls. In study 2, control pigs had a significantly greater frequency of intermediate adipocytes but the milk-fed piglets tended to have a higher frequency of the largest adipocytes. In conclusion, milk has no apparent causal or consistent effect on adipose tissue in growing piglets.

Leishmania detection in sand flies using a field-deployable real-time analytic system.

We describe here the development and evaluation of advanced vector surveillance analytic technologies for real-time leishmaniasis risk assessment. Leishmania genus and visceral leishmaniasis causative agent--specific dual fluorogenic-probe hydrolysis (TaqMan), thermally stable (freeze-dried) polymerase chain reaction assays were developed using field-durable analytic instrumentation. In laboratory testing with a panel of diverse Leishmania species from culture and infected sand flies, the sensitivity and specificity of both assays were 100% concordant with DNA sequencing. In specificity testing with Leishmania genetic near neighbors, clinically significant organisms, and human genomic DNA, no detectable fluorescence above background was observed. Field evaluation was conducted in southern Iraq using wild sand flies. In field testing, Leishmania genus assay was 100% sensitive and 96% specific with a single false-positive result. The visceral leishmaniasis genotype assay was 100% sensitive and 100% specific compared to DNA sequencing. Thermally stable polymerase chain reaction assays vastly simplified transportation and storage. Assay preparation and analysis required less than 2 hours.

Impact of phlebotomine sand flies on U.S. military operations at Tallil Air Base, Iraq: 4. Detection and identification of leishmania parasites in sand flies.

Sand flies collected between April 2003 and November 2004 at Tallil Air Base, Iraq, were evaluated for the presence of Leishmania parasites using a combination of a real-time Leishmania-generic polymerase chain reaction (PCR) assay and sequencing of a 360-bp fragment of the glucose-6-phosphate-isomerase (GPI) gene. A total of 2,505 pools containing 26,574 sand flies were tested using the real-time PCR assay. Leishmania DNA was initially detected in 536 pools; however, after extensive retesting with the real-time PCR assay, a total of 456 pools were considered positive and 80 were considered indeterminate. A total of 532 samples were evaluated for Leishmania GPI by sequencing, to include 439 PCR-positive samples, 80 PCR-indeterminate samples, and 13 PCR-negative samples. Leishmania GPI was detected in 284 samples that were sequenced, to include 281 (64%) of the PCR-positive samples and 3 (4%) of the PCR-indeterminate samples. Of the 284 sequences identified as Leishmania, 261 (91.9%) were L. tarentolae, 18 (6.3%) were L. donovani-complex parasites, 3 (1.1%) were L. tropica, and 2 were similar to both L. major and L. tropica. Minimum field infection rates were 0.09% for L. donovani-complex parasites, 0.02% for L. tropica, and 0.01% for the L. major/tropica-like parasite. Subsequent sequencing of a 600-bp region of the "Hyper" gene of 12 of the L. donovani-complex parasites showed that all 12 parasites were L. infantum. These data suggest that L. infantum was the primary leishmanial threat to U.S. military personnel deployed to Tallil Air Base. The implications of these findings are discussed.

Use of vector diagnostics during military deployments: recent experience in Iraq and Afghanistan.

Vector-borne diseases such as malaria, dengue, and leishmaniasis are a threat to military forces deployed outside of the United States. The availability of specific information on the vector-borne disease threat (e.g., presence or absence of a specific disease agent, temporal and geographic distribution of competent vectors, and vector infection rates) allows for effective implementation of appropriate measures to protect our deployed military forces. Vector diagnostics can provide critical, real-time information crucial to establishing effective vector prevention/control programs. In this article we provide an overview of current vector diagnostic capabilities, evaluate the use of vector diagnostics in Operation Enduring Freedom and Operation Iraqi Freedom, and discuss the concept of operations under which vector diagnostics are employed.

Presence of multiple variants of Borrelia burgdorferi in the natural reservoir Peromyscus leucopus throughout a transmission season.

White-footed mice (Peromyscus leucopus) serve as the principal reservoir for Borrelia burgdorferi and have been shown to remain infected for life. Complex infections with multiple genetic variants of B. burgdorferi occur in mice through multiple exposures to infected ticks or through exposure to ticks infected with multiple variants of B. burgdorferi. Using a combination of cloning and single strand conformation polymorphism (SSCP), B. burgdorferi ospC variation was assessed in serial samples collected from individual P. leucopus during a single transmission season. In individuals with ospC variation, at least seven ospC variants were recognized at each time point. One to four of these variants predominated at each time point; however, the predominant variants seldom remained consistent in an individual mouse throughout the entire sampling period. These results confirmed that mice in southern Maryland were persistently infected with multiple variants of B. burgdorferi throughout the transmission season. However, the presence of multiple ospC variants and the fluctuations in the frequency of these variants indicates that either new ospC variants are regularly introduced to this mouse population and predominate while the existing infections are cleared, or that the variation detected in the genetic profile at different time points reflects a complex mixture of B. burgdorferi populations whose relative frequencies may continually change.

Cleaning and other control and validation strategies to prevent allergen cross-contact in food-processing operations.

Food allergies affect an estimated 10 to 12 million people in the United States. Some of these individuals can develop life-threatening allergic reactions when exposed to allergenic proteins. At present, the only successful method to manage food allergies is to avoid foods containing allergens. Consumers with food allergies rely on food labels to disclose the presence of allergenic ingredients. However, undeclared allergens can be inadvertently introduced into a food via cross-contact during manufacturing. Although allergen removal through cleaning of shared equipment or processing lines has been identified as one of the critical points for effective allergen control, there is little published information on the effectiveness of cleaning procedures for removing allergenic materials from processing equipment. There also is no consensus on how to validate or verify the efficacy of cleaning procedures. The objectives of this review were (i) to study the incidence and cause of allergen cross-contact, (ii) to assess the science upon which the cleaning of food contact surfaces is based, (iii) to identify best practices for cleaning allergenic foods from food contact surfaces in wet and dry manufacturing environments, and (iv) to present best practices for validating and verifying the efficacy of allergen cleaning protocols.

Validation of use of annular once-punched filter paper bloodspot samples for repeat lead testing.

BACKGROUND: Lack of a second sample often precludes the ability to perform repeat lead measurements on filter paper bloodspot samples. We investigated whether annular specimens remaining from once-punched filter paper bloodspot specimens could provide accurate Pb measurements when measurements were scaled for the remainder area relative to the original punch area. METHODS: 50 microl bloodspot specimens were prepared using Pb-spiked EDTA whole blood. After removal of 6 mm punches, bitmap images of the remainder specimens were obtained using a scanner. Image analysis was used to determine the bloodspot area of the remainder sample relative to the area of the original punch. Measurement of Pb for punches and for remainder specimens was performed by ICP-MS. RESULTS: Area-corrected Pb measurements for remainder samples were significantly higher than for the punches, by an average factor of 1.52+/-0.12 (p<0.05, n=28). The difference was due to a discontinuity (an increase) in the per-area Pb at the bloodspot perimeter. Area-corrected results for annular specimens that excluded the perimeter were identical to those of the punch. CONCLUSION: Area-corrected Pb measurement using annular once-punched bloodspot remainder specimens can accurately reproduce lead measurements obtained from the original punch when the bloodspot perimeter area is excluded.

Detection of Borrelia burgdorferi DNA in lizards from Southern Maryland.

Lizards serve as hosts for Ixodes ticks in the western and southeastern United States and may affect the transmission cycles of Borrelia burgdorferi in these regions. In Maryland, the role of lizards in the maintenance and transmission cycle of this pathogen has not been examined. We tested 29 lizards (Sceloporus undulatus and Eumeces spp.) and 21 ticks from these lizards for the presence of B. burgdorferi. Eight lizards were positive by polymerase chain reaction (PCR) for at least one B. burgdorferi-specific marker. This is the first report of B. burgdorferi sensu stricto detected in lizards in the mid-Atlantic region. Although the viability of the B. burgdorferi in these lizards was unconfirmed, recovery of bacterial DNA in a tail snip suggests that the infections in these lizards were disseminated. This study suggests that some lizards indigenous to the mid-Atlantic region may serve as alternative reservoirs for B. burgdorferi. In areas where lizard densities are high, these less efficient reservoirs may affect the enzootic cycle of this tick-borne pathogen.

Co-circulating microorganisms in questing Ixodes scapularis nymphs in Maryland.

Ixodes scapularis can be infected with Borrelia burgdorferi, Anaplasma phagocytophilum, Bartonella spp., Babesia microti, and Rickettsia spp., including spotted-fever group Rickettsia. As all of these microorganisms have been reported in Maryland, the potential for these ticks to have concurrent infections exists in this region. To assess the frequency of these complex infections, 348 I. scapularis nymphs collected in 2003 were screened for these microorganisms by PCR with positives being confirmed by DNA sequencing. Borrelia burgdorferi was detected in 14.7% of nymphs. Anaplasma phagocytophilum (0.3%), Rickettsia spp. (19.5%), and an uncategorized agent (0.9%) was also detected. Dual infections were detected with B. burgdorferi and Rickettsia spp. as well as a triple infection with B. burgdorferi, Rickettsia spp., and an uncategorized agent. Infections with B. burgdorferi and Rickettsia spp. were statistically independent of one another. However, infection with B. burgdorferi and any one of these other microorganisms appears to occur more frequently than by chance alone, probably as a result of shared enzootic cycles. This study confirms that multiple microorganisms co-circulate with B. burgdorferi in I. scapularis in Maryland and demonstrates that Rickettsia spp. and B. burgdorferi circulate independently and at nearly equal frequencies, while A. phagocytophilum and other unrecognized organisms are less common.

Mammal diversity and infection prevalence in the maintenance of enzootic Borrelia burgdorferi along the western Coastal Plains of Maryland.

The primary vector of Borrelia burgdorferi in North America, Ixodes scapularis, feeds on various mammalian, avian, and reptilian hosts. Several small mammal hosts; Peromyscus leucopus, Tamias striatus, Microtus pennsylvanicus, and Blarina spp. can serve as reservoirs in an enzootic cycle of Lyme disease. The primary reservoir in the northeast United States is the white-footed mouse, P. leucopus. The infection prevalence of this reservoir as well as the roles of potential secondary reservoirs has not been established in southern Maryland, a region of low to moderate Borrelia infection in humans. Intensive trapping at 96 locations throughout the western Coastal Plains of Maryland was conducted and we found that 31.6% of P. leucopus were infected with B. burgdorferi. Sequence and phylogenetic analysis revealed that only B. burgdorferi sensu stricto circulated in southern Maryland. Feral house mice and voles also were infected and may serve as secondary hosts. Peromyscus gender, age and month of capture were significantly associated with infection status. Larval I. scapularis were the dominant ectoparasite collected from captured rodents even though host seeking A. americanum and D. variabilis were collected in greater numbers across the sampling region. Our findings illustrate that the enzootic cycle of LD is maintained in the western Coastal Plains region of southern Maryland between I. scapularis and P. leucopus as the dominant reservoir.

National registry for juvenile-onset recurrent respiratory papillomatosis.

BACKGROUND: Juvenile-onset recurrent respiratory papillomatosis (JORRP) is an infrequent but debilitating disease. Because JORRP is uncommon, it has proven difficult for studies at single institutions to accurately evaluate its natural history. OBJECTIVE: To characterize the clinical spectrum of JORRP. DESIGN: Standardized retrospective and prospective medical record abstraction. SETTING: Twenty-two tertiary-care pediatric otolaryngology centers throughout the United States. Patients All patients with JORRP younger than 18 years seen between January 1, 1996, and March 31, 2002. MAIN OUTCOME MEASURES: Demographics, age at diagnosis, anatomic sites of disease, longitudinal disease course, frequency of surgery, need for tracheotomy, and medication history. RESULTS: The registry includes 603 children. The mean age at diagnosis was 4.0 years. The children underwent a mean of 5.1 surgeries annually. Current age, rather than age at diagnosis, was the primary determinant of surgical frequency. The larynx was involved at the time of diagnosis in 96.1% of children, and 87.4% had only 1 anatomic site involved. Children with 1 site involved were significantly older at diagnosis (mean age, 3.9 years) than those with 2 sites (mean age, 2.9 years). Most (74.2%) had stable disease over time, 5.8% showed progression of papillomas to new sites, and 17.9% had no evidence of disease for at least 1 year. Children with disease progression were diagnosed at a significantly younger age than those who remained stable or became disease-free. Children who required tracheotomy were significantly more likely to have progressive disease. CONCLUSIONS: The registry has established the clinical course of JORRP in a large sample representative of the United States. Young age was the most important determinant of disease severity (frequency of surgery, extent of disease at diagnosis, and progression of disease). Addressing questions of pathogenesis and disease course will require a revised data collection instrument and molecular analysis of tissues.

Simultaneous Growth of Listeria monocytogenes and Listeria innocua.

Listeria spp. have been isolated from a wide variety of sources, and in many situations Listeria innocua is more commonly found than Listeria monocytogenes . Growth of three L. monocytogenes strains was studied when inoculated simultaneously with a rhamnose negative L. innocua strain into culture media and cheese sauce. Fraser broth (FB), Trypticase™ soy broth plus 0.6% yeast extract (TSB-YE), University of Vermont medium (UVM) modified Listeria enrichment broth, and cheese sauce were inoculated (ca. 102 cells per ml) and incubated for 24 h; FB, TSB-YE, and cheese sauce at 35°C, UVM at 30°C. Growth of four rhamnose-positive, L. innocua strains was also studied in culture media. Growth of L. monocytogenes was similar to that for L. innocua in TSB-YE or cheese sauce. However, in FB and UVM, L. innocua populations were significantly higher than L. monocytogenes . This occurred when media were inoculated individually or simultaneously. This may explain in part why L. innocua is isolated more frequently than L. monocytogenes from foods and environmental samples.

Spotted-fever group Rickettsia in Dermacentor variabilis, Maryland.

Three-hundred ninety-two adult Dermacentor variabilis were collected from six Maryland counties during the spring, summer, and fall of 2002. Infection prevalence for spotted fever group Rickettsia was 3.8%, as determined by polymerase chain reaction. Single strand conformational polymorphism (SSCP) analysis followed by sequencing indicated that all infections represented a single rickettsial taxon, Rickettsia montanensis.