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J M Reguera

Publications and source records attributed to J M Reguera.

At least 19 recordsLinked to original sources

Rose Bengal test: diagnostic yield and use for the rapid diagnosis of human brucellosis in emergency departments in endemic areas.

The aim of the present study was to analyse the diagnostic yield of the rose Bengal test for the rapid diagnosis of human brucellosis in an emergency department in an area where the disease is endemic. The study included 711 patients diagnosed initially with brucellosis and 270 controls. Brucellosis patients were divided into three groups: group I, individuals with no regular exposure to or history of brucellosis; group II, individuals exposed repeatedly to Brucella infection; and group III, individuals infected with Brucella who had received appropriate treatment during the previous 12 months. Blood cultures were positive for 445 (62.6%) brucellosis patients, while the remaining 266 (37.4%) patients were diagnosed according to clinical and serological criteria. The overall sensitivity of the rose Bengal test was 92.9%. The specificities for groups I, II and III were 94.3%, 91.7% and 76.9%, respectively, with positive likelihood ratios of 16.5, 10.4 and 4.2, respectively. The diagnostic gain after the performance of the rose Bengal test was good or very good in patients with no previous exposure to Brucella or history of brucellosis, but poor in patients who were exposed repeatedly to Brucella or had a history of brucellosis and a low pre-test probability. Use of the rose Bengal test as the sole technique for the diagnosis of brucellosis in endemic areas should be considered very carefully in the context of patients who are exposed repeatedly to Brucella or have a history of brucellosis.

Adolescent↗

Rapid diagnosis of human brucellosis by SYBR Green I-based real-time PCR assay and melting curve analysis in serum samples.

The aim of this study was to develop a LightCycler-based real-time PCR (LC-PCR) assay and to evaluate its diagnostic use for the detection of Brucella DNA in serum samples. Following amplification of a 223-bp gene sequence encoding an immunogenetic membrane protein (BCSP31) specific for the Brucella genus, melting curve and DNA sequencing analysis was performed to verify the specificity of the PCR products. The intra- and inter-assay variation coefficients were 1.3% and 6.4%, respectively, and the detection limit was 5 fg of Brucella DNA (one genome equivalent). After optimisation of the PCR assay conditions, a standard curve was obtained with a linear range (correlation coefficient=0.99) over seven orders of magnitude from 10(7) to 10 fg of Brucella DNA. The LC-PCR assay was found to be 91.9% sensitive and 95.4% specific when tested with 65 negative control samples and 62 serum samples from 60 consecutive patients with active brucellosis. The assay is reproducible, easily standardised, minimises the risk of infection in laboratory workers, and has a total processing time of <2 h. It could therefore form a promising and practical approach for the rapid diagnosis of human brucellosis.

Benzothiazoles↗

Real time polymerase chain reaction: a new powerful tool for the diagnosis of neurobrucellosis.

BACKGROUND/METHODS: We compared the diagnostic yield of a real time polymerase chain reaction (PCR) assay in cerebrospinal fluid (CSF) samples with conventional microbiological techniques for the diagnosis of neurobrucellosis. Following amplification of a 223 bp sequence specific for Brucella genus, melting curve analysis was performed to verify the specificity of the PCR products. RESULTS: All six patients with neurobrucellosis (three meningitis and three meningoencephalitis) had a positive real time PCR assay, whereas CSF cultures and Wright seroagglutination tests were positive in only two and four cases, respectively. Brucella specific amplicons were easily demonstrated by their characteristic melting temperature in all the real time PCR assays. CONCLUSION: LightCycler based real time PCR assay in CSF samples is more rapid and sensitive than conventional microbiological tests. This technique could be useful for the rapid diagnosis of neurobrucellosis.

Adult↗

Tuberculous vertebral osteomyelitis in the new millennium: still a diagnostic and therapeutic challenge.

In order to determine the clinical features and current prognosis of tuberculous vertebral osteomyelitis, the charts of all patients diagnosed with definite or probable tuberculous vertebral osteomyelitis from January 1983 to June 2002 ( n=78) were reviewed. The mean delay to diagnosis was 6.1 months. Sixty-five (83.3%) patients had inflammatory spinal pain, 35 (44.9%) had some neurological deficit, and only 27 (34.6%) had fever. Paravertebral, epidural, and psoas abscesses were detected in 73.1, 65.4, and 24.4% of the cases, respectively. Culture was positive in 48% of the percutaneous biopsies and in 61.7% of the open biopsies. After histological findings were included, the diagnostic yield of percutaneous biopsies was 68%. Fifty-five (70.5%) patients required surgical treatment at some stage of the disease. Although no deaths were directly attributable to tuberculous vertebral osteomyelitis and only 5.1% of patients relapsed, the mean overall hospital stay was 69.1+/-36.9 days, and 30 (38.5%) patients had severe functional sequelae. In conclusion, diagnosis of tuberculous vertebral osteomyelitis requires a high degree of suspicion. Percutaneous biopsy should be undertaken as soon as possible in any patient with compatible symptoms or radiological images in order to initiate suitable therapy.

Adolescent↗

Brucella endocarditis: clinical, diagnostic, and therapeutic approach.

Brucella endocarditis is an uncommon focal complication of brucellosis. Presented here are 11 cases of Brucella endocarditis, all managed uniformly. The median duration of symptoms prior to diagnosis was 3 months. Five patients (45%) had underlying valvular damage, and in six (55%) endocarditis involved a normal valve. There was a predominance of aortic involvement (82%) and a high incidence of left ventricular failure (91%). Diagnostic suspicion was essential in order to test blood cultures correctly, which in this series were positive in 63% of the patients. Surgical treatment was undertaken in eight patients (72%), all with aortic involvement and left ventricular failure impossible to control with medication. One patient died during the immediate postoperative period. All the other patients received antibiotic therapy for 3 months, with no signs of relapse of the infection or malfunction of the prosthesis during a minimum follow-up period of 24 months.

Adult↗

High mortality related with Staphylococcus aureus bacteremia after liver transplantation.

The aim of the present study was to analyze the characteristics of bacteremia occurring in liver-transplant patients in Andalusia, Spain, during the 1990s. At the three participating hospitals, 405 liver transplantations were performed during the study period, and 119 bacteremic episodes were observed following 91 of them (22.4%, 29.4 episodes/100 liver transplants). Gram-positive organisms were the predominant bacteria isolated in cases of early-onset bacteremia (70.7%, P=0.04). The most common sources of bacteremia were the abdomen (33.6%) and intravascular catheters (22.7%), but frequently the source of bacteremia was unknown (31.9%). Mortality at 30 days was 21%. Isolation of Staphylococcus aureus was the only independent risk factor for mortality (relative risk, 3.13; 95% confidence interval, 1.3-7.5; P=0.01). These results indicate that control measures are required in order to reduce the incidence of gram-positive bacteremia and catheter-related infection in this patient population. The observed etiology must be considered when empirical antimicrobial therapy is indicated while awaiting blood-culture results.

Adult↗

Diagnostic yield of a PCR assay in focal complications of brucellosis.

In order to evaluate the diagnostic yield of a PCR assay for patients with focal complications of brucellosis, we studied by PCR and by conventional microbiological techniques 34 nonblood samples from 32 patients with different focal forms of brucellosis. The samples from patients with brucellosis were paired to an equal number of control samples from the same locations of patients whose illnesses had different etiologies. Thirty-three of the 34 nonblood samples (97%) from the brucellosis patients were positive by PCR, whereas Brucella spp. were isolated from only 29.4% of the conventional cultures. For 11.4% of the patients, the confirmatory serological tests were either negative or showed titers below the diagnostic range. Two patients (6.2%) from the control group, both with tuberculous vertebral osteomyelitis, had a positive PCR result. The brucella PCR of blood from these two patients was also positive, and the two strains of Mycobacterium tuberculosis isolated were analyzed by the brucella PCR, with no evidence of amplification. These results show that the PCR assay is far more sensitive than conventional cultures, and this, coupled with its speed and reduction in risk to laboratory workers, makes this technique a very useful tool for the diagnosis of focal complications of brucellosis.

Adult↗

Postoperative spondylodiskitis: etiology, clinical findings, prognosis, and comparison with nonoperative pyogenic spondylodiskitis.

We studied 31 cases of postoperative pyogenic spondylodiskitis (POS), comparing them with 72 cases of nonpostoperative pyogenic spondylodiskitis (NPOS). POS represents 30.1% of cases of pyogenic spondylodiskitis. The onset of symptoms occurred an average (+/-SD) of 27.7 (+/- 25.3) days following surgery. Predisposing factors were less frequent in POS than NPOS cases (P = .002). Neurological complications and inflammatory signs in the spine were more frequent with POS than with NPOS (P = .002 and P < .00001). Coagulase-negative Staphylococcus and anaerobic bacteria were more frequent in POS than in NPOS (P = .0001 and P = .05). Percutaneous bone biopsies yielded the etiology in 66.7% of cases, open bone biopsies in 100%, blood cultures in 55.6%, and cultures of adjacent foci in 94.4%. Eleven patients (35.5%) were cured with antimicrobial treatment, but surgical treatment was necessary in 64.5%. No relapses or deaths were recorded. Seventeen patients (54.8%) had severe functional sequelae, which were associated with inflammatory signs in the spine (P = .033), higher levels of leukocytosis (P = .05), higher erythrocyte sedimentation rates (P = .05), and paravertebral abscesses (P = .04).

Adolescent↗

Posttreatment follow-Up of brucellosis by PCR assay.

In order to evaluate the usefulness of a peripheral blood PCR assay in the posttreatment follow-up of brucellosis, a cohort of 30 patients was studied by means of blood cultures, rose Bengal, seroagglutination, Coombs' antibrucella tests, and PCR assay at the time of diagnosis, at the end of treatment, and 2, 4, and 6 months later. Of the 29 patients whose PCR assays were initially positive, 28 (96.5%) were negative at the conclusion of the treatment. PCR was positive for the two patients who had relapses and negative for another four who had suspected but unconfirmed relapses. PCR was negative for 98.3% of the follow-up samples from those patients who had a favorable evolution. In conclusion, PCR appears to be a very useful technique, not only for the initial diagnosis of the disease, but also for posttreatment follow-up and the early detection of relapses.

Adolescent↗

Pyogenic, tuberculous, and brucellar vertebral osteomyelitis: a descriptive and comparative study of 219 cases.

OBJECTIVES: To describe a large series of patients with vertebral osteomyelitis (VO), and to compare the clinical, biological, radiological, and prognostic features of pyogenic (PVO), tuberculous (TVO), and brucellar vertebral osteomyelitis (BVO). METHODS: A retrospective multicentre study, which included 219 adult patients with VO with confirmed aetiology, who were diagnosed between 1983 and 1995 in two tertiary care centres. Of these patients, 105 (48%) had BVO, 72 (33%) PVO, and 42 (19%) TVO. RESULTS: One hundred and forty eight (67.6%) patients were male and 71 (32.4%) female. The mean (SD) age was 50.4 (16.4) years (range 14-84) and the mean (SD) duration of symptoms before the diagnosis was 14 (16.8) weeks. In 127 patients (57.9%) the vertebral level involved was lumbar, in 70 (31.9%) thoracic, and in 16 (7.3%) cervical. One hundred and nineteen patients (54.4%) received only medical treatment and 100 (45.6%) required both medical and surgical treatment. The presence of diabetes mellitus, intravenous drug abuse, underlying chronic debilitating diseases or immunosuppression, previous infections, preceding bacteraemia, recent vertebral surgery, leucocytosis, neutrophilia, and increased erythrocyte sedimentation rate (ESR) were significantly associated to PVO. A prolonged clinical course, thoracic segment involvement, absence of fever, presence of spinal deformity, neurological deficit, and paravertebral or epidural masses, were significantly more frequent in the group of TVO. The need for surgical treatment and the presence of severe functional sequelae were more frequent in the groups of PVO and TVO. CONCLUSION: There are significant clinical, biological, radiological, and prognostic differences between BVO, PVO, and TVO. These differences can point to the causal agent and orient the initial empirical medical treatment while awaiting a final microbiological diagnosis.

Adolescent↗

Complications associated with Brucella melitensis infection: a study of 530 cases.

We carried out a prospective study of 530 patients older than 14 years of age with brucellosis. We describe the incidence and clinical features of the focal forms of the disease, analyzing some of the possible factors associated with their appearance. One hundred sixty-nine patients (31.9%) had a focal form or complication. Osteoarticular complications were the most frequent, totaling 113 cases (66%), followed by genitourinary with 18 cases (5.1% of males), hepatic (2.5%), neurologic (1.7%), and heart (1.5%). Nine patients (1.7%) had more than 1 complication. In a multivariate analysis, diagnostic delay greater than 30 days (OR 2.0), ESR > 40 mm/hr (OR 1.9), and levels of alpha-2 globulin > 7.5 g/L (OR 6.8) were statistically significant independent variables associated with the presence of focal forms. Twenty-five patients with complications (14.8%) required surgical treatment. The relapse rate was 3.6% for those patients without complications and 4.1% for patients with focal forms (p > 0.05). However, when therapeutic failure, relapses, and mortality were considered together, the risk of an unfavorable evolution was significantly greater in patients with focal forms (10.6% versus 3.6% in patients without complications; OR 1.9, 95% CI 1.4-7.1, p < 0.005). Given the worse prognosis, knowledge and early diagnosis of the focal forms of B. melitensis infection is especially important.

Adolescent↗

Phagocytic cell function in active brucellosis.

In this study, we analyzed phagocytic cell function in 51 patients with active brucellosis and its relationship with different clinical, serological, and evolutionary variables. A control group was made up of 30 blood donors of similar geographic extraction, age, and sex, with no previous history of brucellosis or known exposure ot the infection or specific antibodies. The investigations were carried out at the time of diagnosis, at the conclusion of treatment, and after 6 months of follow-up. Polymorphonuclear leukocyte adherence and nitroblue tetrazolium reduction in response to Brucella antigen were significantly increased in the patients at the time of diagnosis with respect to the control group. In contrast, chemotaxis in response to Brucella antigen and phagocytosis were significantly reduced in the patients with respect to the control group. The alterations in phagocytic cell function were greater in patients with bacteremia, with focal forms of the disease, or with a longer diagnostic delay. Most of these initial alterations tended to normalize with treatment, indicating their transient character.

Adolescent↗

[Evaluation of the Chromotitre EIA test in the diagnosis of human brucellosis].

BACKGROUND: The aim of the study was to evaluate the diagnostic efficacy of Chromotitre EIA test for the diagnosis of human brucellosis and compare the same with other classical serologic test. METHODS: A prospective study was performed in 50 patients with active brucellosis. Thirty blood donors, 64 patients with different neoplastic and autoimmune infectious processes, 20 patients with history of brucellosis and 8 subjects with continuous exposure to Brucella at work were analyzed as the control group. RESULTS: Forty-five patients with brucellosis (90%) presented a positive IgM or IgG ELISA, 32 (62%) only IgM, 34 (68%) only IgG and 22 (44%) both immunoglobulins were positive. The sensitivity and specificity of ELISA test jointly evaluating IgM and IgG was 90 and 68%, respectively with these numbers being 62 and 98% and 68% and 38% for ELISA IgM and ELISA IgG. A moderate correlation was found between ELISA IgM with Bengal's Rose test (r = 0.53, p = 0.003) and sero-agglutination (r = 0.63, p = 0.0001) and ELISA IgG with the Coombs test (r = 0.55, p = 0.003). Only acceptable concordance was observed between ELISA IgM and sero-agglutination (kappa = 0.55, p = 0.0001). CONCLUSIONS: The ELISA test evaluated was very useful for the detection of IgM antibodies but was found to be insufficient with respect to IgG antibodies. Despite the slight diagnostic efficacy of the ELISA IgG the combined parallel use of both immunoglobulins achieved a performance similar to that achieved with the classical tests.

Adolescent↗