PubMed Health⌕ Search

Biomedical subjects

D J Baumgardner

Publications and source records attributed to D J Baumgardner.

At least 19 recordsLinked to original sources

Studies on the molecular ecology of Blastomyces dermatitidis.

The microecology of Blastomyces dermatitidis, the dimorphic etiologic agent of the potentially fatal systemic fungal infection, blastomycosis, is not well defined. Blastomyces dermatitidis may occur periodically at natural sites, perhaps aided by rotting organic material, animal droppings and physical changes. Semi-quantitative growth studies of B. dermatitidis on 2% agar plates determined the ability to utilize or tolerate a variety of substrates including simple and complex molecules as carbon source, and organic and inorganic nitrogen sources. Allantoin, creatinine, quanidoacetic acid, guanidine and cysteine may be used as sole nitrogen source. Allantoin in combination with dextrose, glycerol, lichenen, celloboise and other wood by-products support growth of B. dermatitidis at room temperature. The nutritional conversion of the fungus to the yeast form at room temperature, well demonstrated on allantoin/glycerol/yeast extract media, appears to be affected by certain inorganic compounds. The organism tolerates low to moderate levels of alpha-pinene, tannic acid, shikimic acid, veratryl alcohol, vanillic acid, and polyethyleneglycol-200. There are significant differences among isolates regarding growth on various substances at 20 degrees and 37 degrees centigrade. It appears that a variety of wood by-products and animal waste substrates, in combination, support the growth of B. dermatitidis. Their role in the ecological niche of B. dermatitidis, and the importance of nutritional dimorphism in the natural environment warrants further investigation.

Allantoin↗

Blastomycosis: more evidence for exposure near one's domicile.

BACKGROUND: Our previous publications on the epidemiology of blastomycosis suggested that the etiologic organism, Blastomyces dermatitidis, may be acquired at home, however this view was challenged in an editorial. METHODS: 1) Field study of 2 properties that preliminarily suggested disease acquisition in the home. Owner interviews, site visits and environmental cultures using our in-vitro technique were used. 2) An address registry of human and dog blastomycosis cases was constructed from extensions of our previously published case series. 3) Literature review. RESULTS: 1) Blastomycosis occurred in a dog (December, 1998) and then a cat confined to its home (September, 1999), from a household in urban Manitowoc County, WI; and additionally in a house-confined cat (July, 1998) at a home in Milwaukee, WI. Interviews implicated the basement and the attic or basement, respectively, as the most likely source of infection at these homes. Environmental cultures were negative for Blastomyces. Of the 229 domiciles in the registry, a minimum of 27 (12%) were associated with more than one blastomycosis case, 10 sites with more than two and 7 with more than three. In 4 domiciles, repeat cases occurred in different families. Most cases were separated by 1 year or more (range: 3 weeks to 7 years). Recent case series reveal a minority of outdoor activities and occupations among humans with blastomycosis. The organism has been isolated from an inhabited yard and from a house being razed. CONCLUSIONS: There appears to be growing evidence that blastomycosis may be acquired at home, and that B. dermatitidis may be relatively persistent on certain properties.

Animals↗

Normocytic anemia.

Anemia is a common problem that is often discovered on routine laboratory tests. Its prevalence increases with age, reaching 44 percent in men older than 85 years. Normocytic anemia is the most frequently encountered type of anemia. Anemia of chronic disease, the most common normocytic anemia, is found in 6 percent of adult patients hospitalized by family physicians. The goals of evaluation and management are to make an accurate and efficient diagnosis, avoid unnecessary testing, correct underlying treatable causes and ameliorate symptoms when necessary. The evaluation begins with a thorough history and a careful physical examination. Basic diagnostic studies include the red blood cell distribution width, corrected reticulocyte index and peripheral blood smear; further testing is guided by the results of these studies. Treatment should be directed at correcting the underlying cause of the anemia. A recent advance in treatment is the use of recombinant human erythropoietin.

Adult↗

Clues to the presence of pathogenic fungi in certain environments.

The presence of various pathogenic fungi in rather unsuspected hosts and environments has always attracted the attention of the scientific community. Reports on the putative role of animals in fungal infections of humans bear important consequences on public health as well as on the understanding of fungal ecology. Fungi are ubiquitous in nature and their great capacity for adaptation allows them to survive and indeed, to thrive, in plants, trees and other natural substrata. Nonetheless, we are just beginning to learn the significance that these diverse fungal habitats have on the increasing number of immunosuppressed individuals. The accidental or permanent presence of fungi in animals, plants, soils and watercourses should not be taken too lightly because they constitute the source where potential pathogens will be contracted. If those fungal habitats that carry the largest risks of exposure could be defined, if seasonal variations in the production of infectious propagules could be determined, and if their mode of transmission were to be assessed, it would be possible to develop protective measures in order to avoid human infection. Additionally, unsuspected avenues for the exploration of fungal survival strategies would be opened, thus enhancing our capacity to react properly to their advancing limits. This paper explores several ecological connections between human pathogenic fungi and certain animals, trees, waterways and degraded organic materials. The occurrence of such connections in highly endemic areas will hopefully furnish more precise clues to fungal habitats and allow the design of control programs aimed at avoiding human infection.

Animals↗

The in vitro isolation of Blastomyces dermatitidis from a woodpile in north central Wisconsin, USA.

Environmental isolations of the dimorphic fungus, Blastomyces dermatitidis, the aetiologic agent of blastomycosis are rare, and have usually involved animal inoculation techniques. We report the in vitro isolation of B. dermatitidis from a woodpile in November 1997, from a private property in a highly endemic area of north central Wisconsin, USA. The woodpile was 73 m from the Wisconsin River and 5 m from a kennel which had housed nine dogs over the past 14 years, four of which had been diagnosed with blastomycosis. One of 19 samples from the property yielded B. dermatitidis after 37 degrees C incubation in a neutral aqueous solution of allantoin, Tween-80, potassium phosphate, magnesium sulphate, penicillin and streptomycin followed by plating on yeast-extract phosphate agar at 20 degrees C. Refinements of this technique may help further elucidate the ecological niche of B. dermatitidis.

Animals↗

Epidemiology of human blastomycosis in Vilas County, Wisconsin. II: 1991-1996.

PURPOSE: A previous report identified Vilas County, Wisconsin, as an area highly endemic for blastomycosis based on a case series 1979-90. This study was done to compare the epidemiologic features of persons with this disease over the following six years. METHODS: Compilation of data from the 47 mandatory physician/laboratory case reports of blastomycosis, disease onset 1991-96, received at the Vilas County Health Department; case mapping by site visit; and statistical comparison to the previous series. RESULTS: The estimated mean annual incidence rate for Vilas County during 1991-96, 40/100,000, remains unchanged from 1984-90. Cases were again disproportionately represented in the southeast corner of the county, and 36/46 lived within 1/4 mile of water. There was a trend toward a higher proportion of female cases in this study (27/47) compared to the prior report (28/73; P = 0.06); the mean age, 47 years, did not differ. Among 32 patients whose activities were recorded, a minority engaged in hunting (4), fishing (4) and gardening (12) prior to disease onset; but 19/32 recalled excavation prior to exposure compared to 17/60 in 1979-90 (P < 0.01). Among cases with a pulmonary presentation, winter onset cases (3/40) were significantly fewer than in 1979-90 (19/55). However, over the entire 18 years there was no disproportionately represented season. CONCLUSIONS: In highly endemic Vilas County, the mean annual incidence of human blastomycosis appears stable over the past 13 years. A combined case series of 18 years reveals no predilection by gender or season of onset.

Adolescent↗

Quality-of-life in technology-dependent children receiving home care, and their families--a qualitative study.

PURPOSE: This qualitative study explored quality-of-life (QL) issues among Wisconsin's technology-dependent children and their families. METHODS: Five semi-structured focus groups were held with parents, siblings and health care workers of home-dwelling children dependent upon technology such as tracheostomy, ventilator support and gastrostomy tube feedings. Focus group transcripts were analyzed using an editing style format, with each author as an independent analyst. RESULTS: QL for the child was seen as a relative term, defined within the family, dependent upon the availability of services; and expressed in terms of physical comfort and function, and integration of the child into the family and community. Positive QL aspects for families include: growth as individuals, intrinsic rewards from the child and appreciation of others with handicaps. Negative impacts on family QL include: physical and mental anguish (e.g., exhaustion, suicidal ideation, back injuries), inhibitions of normal family functions, and isolation. Home nursing was highly valued despite lack of privacy. A number of ethical issues emerged including ineffective communication and lack of QL discussions during the child's acute treatment, end-of-life decisions, and potential cuts in Medicaid services. The latter issue prompted fear of poverty and divorce among siblings. CONCLUSIONS: Technology appears to exceed the sociological and ethical components of the care of these children, and QL is defined in terms of physical comfort, functional status, adequate services, and family/community integration. Parents assume an ambiguous medical role with their child, and need respite care and advocacy from their health care team.

Adult↗

Establishing proficiency in flexible sigmoidoscopy in a family practice residency program.

BACKGROUND AND OBJECTIVES: Fiberoptic flexible sigmoidoscopy (FFS) is widely used by family physicians to evaluate abdominal problems and screen for colorectal cancer. We evaluated data on exams performed by family practice residents to determine the number of supervised procedures needed for technical proficiency at FFS. METHODS: We reviewed data recorded from all FFS procedures done at a family practice residency from October 1986-July 1994. RESULTS: A total of 262 exams were performed by 55 residents at the Family Practice Center. There was modest correlation between increasing numbers of exams and increased unassisted depth of insertion (UDI). Maximum UDI was achieved after 10-15 supervised exams. Factors such as patient gender, prior surgery, and preparation quality were also significantly correlated with UDI. Significant differences in training experience and patient selection were seen between male and female residents. CONCLUSIONS: Maximal UDI is reached after 10-15 procedures. Differences in training experiences and successful UDI based on resident gender should be studied further.

Adolescent↗

Epidemiology of blastomycosis in a region of high endemicity in north central Wisconsin.

The clinical and epidemiologic features of 73 patients with laboratory-confirmed blastomycosis who were identified over an 11-year period in North Central Wisconsin are presented. Pulmonary disease was the sole manifestation in 77% of patients. More than one-half of all patients had symptoms that included fever, cough, weight loss, night sweats, and pleuritic chest pain. Virtually all were previously healthy, and most did not have an outdoor occupation. However, 82% of these patients lived or had visited within 500 m of rivers or associated waterways. The majority experienced the onset of symptoms between December and April. The estimated mean annual incidence rate of infection for Vilas County was 40.4 cases per 100,000 persons, and that for the largest city in the county was 101.3 cases per 100,000 persons. Several areas with an exceptionally high incidence of the infection were observed. We suggest that, in regions where blastomycosis is hyperendemic, clinical disease is most often pulmonary and occurs in immunocompetent individuals and that residence near an ecological focus may be a greater risk factor for acquisition of blastomycosis than is occupation.

Adolescent↗

The infant with a reddish diaper.

The infant with a reddish diaper presents a diagnostic challenge to the primary care physician. As described by Dr Baumgardner, the cause may be benign, but more ominous disorders must be ruled out.

Crystallization↗

Persistent urticaria caused by a common coloring agent.

As this case illustrates, foods or drugs may be ignored as possible causes of urticaria when they are not commonly accepted offenders or when they previously have been consumed with no adverse effect. In some instances, an additive or dye in a food or drug may be responsible for the reaction. In addition, a change of brands or dosage form of a drug may provoke urticaria or other reactions in sensitive individuals.

Azo Compounds↗

Abdominal pain. Chlamydia as culprit.

Chlamydia trachomatis infection in the lower part of the genital tract of young girls and women may ascend to produce endometritis, salpingitis, perihepatitis, and other localized or generalized abdominal diseases. The resultant pain syndromes mimic a number of other common conditions that must be differentiated. A careful history and physical examination, with attention to historical and physical evidence of sexually transmitted disease, will alert the clinician to the possibility of chlamydial infection. Laboratory tests for C trachomatis may be helpful. However, tests of specimens from the lower genitourinary tract may yield negative results in patients with disease of the upper part of the genital tract and abdomen. Prompt recognition and treatment not only alleviate pain but also may help prevent inflammatory sequelae such as chronic painful adhesions, small-bowel obstruction, and tubal infertility. Costly workups and unnecessary surgery may also be avoided.

Abdomen↗