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D J Sexton

Publications and source records attributed to D J Sexton.

At least 91 records · Page 5Linked to original sources
PubMed1994

Dermatologic manifestations of arthropod-borne diseases.

The arthropod-borne rickettsial, borrelial, and bacterial diseases of North America are a diverse group of disorders that produce a wide variety of cutaneous abnormalities. These dermatologic abnormalities are often valuable clinical clues that may reveal or suggest the correct diagnosis to the astute clinician. We review the usual and unusual dermatologic manifestations of Rocky Mountain spotted fever, murine and sylvatic typhus, rickettsialpox, ehrlichiosis, Lyme disease, tick-borne relapsing fever, Colorado tick fever, and tularemia. In some of these diseases, skin manifestations may be diagnostic; in others, dermatologic findings may be the initial and only clues that leads to the initiation of life-saving therapy. In other arthropod-borne infections, the appearance or evolution of the skin rash may be characteristic enough to suggest the proper diagnosis.

Animals↗
PubMed1994

The use of a polymerase chain reaction as a diagnostic test for Rocky Mountain spotted fever.

A polymerase chain reaction (PCR) for amplifying ribosomal DNA of Rickettsia rickettsii was performed on blood clots and urine samples from 10 patients with suspected Rocky Mountain spotted fever (RMSF) and five controls with nonrickettsial diseases. The results of this PCR-based procedure were positive in four of the five patients with probable RMSF, but reamplification was required in three patients. Rickettsia rickettsii was grown from the blood of two of these four patients. The urine from one patient was also PCR-positive. These results confirm earlier findings that the PCR can detect R. rickettsii, but the need for reamplification indicates that the lack of sensitivity is a serious limitation in the usefulness of the PCR as a clinical diagnostic test.

Bacteremia↗
PubMed1993

A case-control study of nosocomial ampicillin-resistant enterococcal infection and colonization at a university hospital.

OBJECTIVE: To assess risk factors for colonization and nosocomial infection with ampicillin-resistant enterococci (ARE). DESIGN: Patients with ampicillin-resistant enterococci were compared retrospectively by logistic regression analysis with controls harboring susceptible strains. ARE were characterized by whole plasmid DNA analysis and restriction enzyme analysis of plasmid (REAP) DNA with EcoRI. SETTING: The study was done at a 1,125 bed, tertiary-care teaching hospital in North Carolina with patients from whom enterococci were isolated from June 1, 1989, to March 30, 1991. PATIENTS: The final study group comprised 44 cases with nosocomially-acquired colonization or infection with ARE and 100 controls with ampicillin-susceptible strains. Clinical and epidemiological risk factors for ARE were abstracted by chart review. RESULTS: After controlling for age and site of infection, patients with ARE were more likely to have been admitted previously to our hospital and to have received third-generation cephalosporins and clindamycin. However, only advanced age and clindamycin therapy were independently associated with presence of ARE. REAP with EcoRI showed 20 groups of enterococci on 19 different wards. CONCLUSIONS: These results suggest that ARE are endemic and multifocal in origin in our hospital and that advanced age and use of clindamycin are important selective risk factors for ARE colonization and infection.

Age Factors↗
PubMed1993

Rocky Mountain spotted fever complicated by gangrene: report of six cases and review.

Although mortality due to fulminant Rocky Mountain spotted fever (RMSF) is well appreciated, the ability of the disease to cause survivors to become permanently disabled is not as widely known. We report six cases of RMSF complicated by gangrene. Although four patients required multiple limb and/or digital amputations, only one death resulted. Our review of the English-language literature revealed 23 additional cases of RMSF complicated by gangrene. Pathophysiologically, gangrene is most likely related to small-vessel occlusion. Skin necrosis and gangrene in association with RMSF are the extreme end on a continuum from reversible to irreversible skin and tissue damage caused by Rickettsia rickettsii. Most patients with RMSF have a typical skin rash that resolves without sequelae. Some patients develop minute cicatrices marking the location of focal cutaneous necrosis; for other patients, digital ischemia occurs transiently or evolves to produce severe ischemic changes without gangrene that result in permanent impairment. At the far end of this clinical continuum are patients who develop gangrene requiring amputation.

Adult↗
PubMed1993

Postoperative pubic osteomyelitis misdiagnosed as osteitis pubis: report of four cases and review.

Osteitis pubis is a painful inflammatory process resulting in bony destruction of the margins of the symphysis pubis. Despite six decades of speculation, the pathogenesis of, criteria for diagnosis of, natural history of, and optimal therapy for osteitis pubis remain controversial. We present four cases of postoperative pubic osteomyelitis that were initially thought to be typical cases of osteitis pubis. These cases illustrate that pubic osteomyelitis can mimic the principal features of osteitis pubis including characteristic pelvic pain and gait disturbance, symmetrical bony destruction of the symphysis pubis, absence of fever, a long interval between surgery and onset of symptoms, lack of response to antimicrobial therapy, and apparent spontaneous cure. We believe that many previously reported cases of osteitis pubis were actually cases of unrecognized pubic osteomyelitis. We advise an aggressive diagnostic approach to cases of apparent postoperative osteitis pubis including biopsy and needle aspiration of the symphysis pubis guided by computer-assisted tomography. If cultures of biopsy specimens are not diagnostic, open biopsy of the symphysis pubis is recommended.

Adult↗
PubMed1993

Brazilian spotted fever in Espirito Santo, Brazil: description of a focus of infection in a new endemic region.

Although Brazilian spotted fever is known to occur in several adjacent states, infection with spotted fever group (SFG) rickettsiae has not previously been documented in the Brazilian state of Espirito Santo. We report a cluster of two proven and four suspected cases of Brazilian spotted fever in a small valley near Colatina, Espirito Santo. Four patients died without confirmatory serologic or pathologic studies. The two surviving patients had serologic and/or pathologic evidence of infection with SFG rickettsiae. Results of a survey done in 1991 confirmed the presence of antibodies reactive with SFG rickettsiae in the serum of dogs living in this region. Two of 25 dogs had elevated microimmunofluorescent antibody titers (1:64 and 1:256). Both seropositive dogs were pets of the index cases and lived in the valley where all six human cases were presumed to have acquired their infections. These cases and the results of the canine serosurvey suggest that a focus of virulent disease exists in an area not previously known to be endemic for SFG rickettsiae.

Adult↗
PubMed1992

Glutathione reductases from a variety of sources are inhibited by physiological levels of glutathione.

1. Glutathione reductase from human platelets, bovine intestinal mucosa, yeast and E. coli were inhibited in vitro by physiological levels of reduced glutathione with IC50s of 6.61 mM, 2.92 mM, 2.40 mM and 12.11 mM, respectively. 2. A steady-state kinetic examination revealed that glutathione inhibited the NADPH oxidation (at constant [glutathione-disulphide]) catalysed by the eucaryotic enzymes uncompetitively, whereas the E. coli enzyme appeared unaffected by glutathione concentrations of up to 10 mM. 3. With respect to glutathione inhibition of glutathione-disulphide reduction (at constant [NADPH]), the human enzyme was inhibited uncompetitively; the bovine and yeast enzymes displayed apparent mixed hyperbolic inhibition; the E. coli enzyme was inhibited competitively.

Animals↗
PubMed1992

Rocky Mountain "spotless" and "almost spotless" fever: a wolf in sheep's clothing.

In 10 (10.8%) of 93 laboratory-confirmed or probable cases of Rocky Mountain spotted fever seen at Duke University Medical Center from 1969 to 1991, illness without rash or fleeting or atypical skin eruptions were noted. Data from these 10 cases and 33 similar previously reported cases of Rocky Mountain "spotless" or "almost spotless" fever support the premise that human Rickettsia rickettsii infection has a broader spectrum than that indicated by its classic description. Sixty-one percent of patients with Rocky Mountain spotless or almost spotless fever have been men. Two-thirds have been black. Although in some cases the absence of rash may be due to the prompt institution of therapy with chloramphenicol or tetracycline, in others long delays in recognition of the disease and treatment occurred, resulting in the deaths of 53% of patients. On the basis of outcome in the cases reviewed, empirical administration of chloramphenicol or a tetracycline to selected patients is justifiable (including those patients with severe organ dysfunction), even if they have no rash, a transient rash, or a rash of unusual distribution. Indeed, without such therapy, patients with spotless or almost spotless fever may die. Recognizing such atypical cases is analogous to seeing a wolf in sheep's clothing--intuition, experience, knowledge, and a high index of suspicion are required.

Adolescent↗
PubMed1991

Twice daily intramuscular imipenem/cilastatin in the treatment of skin and soft tissue infections.

One hundred and two patients were enrolled in an open-label evaluation of intramuscular imipenem/cilastatin using doses of either 500 or 750 mg every 12 h in the treatment of mild to moderately severe skin and soft tissue infections. Seventy-four of 102 patients were clinically evaluable. Thirty-one patients had abscesses, 20 had cellulitis and 23 had wound infections. One hundred seventy-eight isolates were recovered from these 74 patients (average 2.4 isolates/patient). Sixty of 74 evaluable patients (82%) were cured; 12 of 74 (16%) were improved. Two patients failed to improve. Therapy was well tolerated. Adverse effects occurred in 8 patients. All of these effects were minor, and none required discontinuation of therapy. Eighty-two percent of patients reported no pain with injections. Therapy did not need to be interrupted or discontinued in the remaining 18% of patients reporting moderate local pain with injections. Peak and trough serum imipenem levels were measured in 15 patients receiving a 500-mg intramuscular dose of imipenem/cilastatin. The mean peak imipenem concentration in 15 patients was 10.7 micrograms/ml (range 3.3-17.8); the mean trough concentration was 2.1 micrograms/ml (range 0.8-4.9). The trough levels were higher than those found in healthy volunteers and may reflect the age and mild renal dysfunction in this group of treated patients. Imipenem/cilastatin used for mild or moderate skin and soft tissue infections was both efficacious and well tolerated. Intramuscular therapy with this agent offers advantages over intravenous therapy because of its long apparent half-life and pharmacokinetics.

Abscess↗
PubMed1991

Prevalence of antibodies to spotted fever group rickettsiae in dogs from southeastern Australia.

Recent epidemiologic data suggests that Rickettsia australis, the cause of Queensland tick typhus, is present in southeastern Australia. In order to further confirm this observation, a canine serosurvey was undertaken to determine if naturally occurring antibodies were present in pet and farm dogs from this newly-recognized endemic area. Thirty-five of 312 surveyed dogs (11.2%) had indirect immunofluorescent antibody titers of 1:64 or greater against R. australis antigen. Positive control sera were obtained from two dogs experimentally inoculated with R. australis. One of these dogs was serially sampled and a rickettsemia could not be documented. None of 26 control sera obtained from dogs from South Australia, New Zealand, western Victoria, or North Carolina had antibody titers greater than or equal to 1:64. These results suggest that spotted fever group rickettsiae are present in Southeastern Australia.

Animals↗
PubMed1990

Randomized, double-blind trial of cefonicid and nafcillin in the treatment of skin and skin structure infections.

We compared treatment with one daily intravenous dose of cefonicid and multidose nafcillin in 65 patients with severe infections of the skin or skin structure. Clinical cure or improvement was achieved in 91% of the patients given cefonicid and in 87% of the patients given nafcillin (P = 0.97). The use of cefonicid may allow outpatient therapy of some severe infections.

Adolescent↗
PubMed1990

Rocky Mountain spotted fever. A clinical review based on 48 confirmed cases, 1943-1986.

We reviewed 48 cases of Rocky Mountain spotted fever seen between 1943 and 1986. The data provided a view of the diverse presentations and manifestations of this disease. Exposure to a rural environment or to dogs was the rule, and over two-thirds of patients specifically remembered tick exposure. Clinical presentation was highly variable. Although fever, headache, and rash were each common, only 62% had the complete triad. Neurological symptoms and signs were common in this series. Cerebrospinal fluid abnormalities, particularly leukocytosis, were the rule in those patients who underwent lumbar puncture. Neurologic sequelae occurred in several patients. Multiple other organ systems were involved at presentation or during the course of illness--gastrointestinal, cardiovascular, pulmonary, renal, muscular, hematologic. These manifestations could, and often did, confuse physicians seeing these patients initially. They further accounted for the diverse complications seen. Outcome was good in this series. Mortality rate was 2%, and most patients recovered without sequelae. However, morbidity during hospitalization was often severe. Even in an endemic area with high index of suspicion, the diagnosis of RMSF was often delayed, usually because of failure of the physician to consider this possibility at initial presentation. This series emphasizes the importance of considering RMSF in any febrile patient in an endemic area, regardless of "atypical" presentation or apparent lack of tick exposure.

Adolescent↗