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J Labarca

Publications and source records attributed to J Labarca.

17 recordsLinked to original sources
PubMed2001

[Infection of ascending aortic graft: treatment with surgical cleaning, graft preservation and transposition of muscle flaps. Report of two cases].

Mediastinitis with graft infection is a serious complication of ascending aorta replacement. We report two cases of graft infection, treated with surgical cleaning, graft preservation and transposition of muscle flaps. A 62 years old male was admitted 34 days after an ascending aortic grafting due to a sternal dehiscence and mediastinitis. Antimicrobial treatment was started and a surgical cleaning performed, leaving an open sternotomy. Three days later, the thoracic cavity was closed with a rectus abdominis muscle flap. After 23 months of follow up, the patient is well and without evidence of infection. A 74 years old male was subjected to an aortic valve and ascending aorta replacement and a myocardial revascularization. In the postoperative period, the patient developed septic signs, and a purulent drainage. A CAT scan showed a liquid collection surrounding the aortic graft. On tW Sixteenth postoperative day, a surgical cleaning was performed and the thorax was closed with the pectoralis major muscle. After 10 months of follow up, the patient is in Good condition and without evidence of infection.

Aged↗
PubMed2001

[Diagnosis of Clostridium difficile diarrhea: in search of a more efficient clinical focus].

BACKGROUND: The clinical parameters for the suspicion of Clostridium difficile infections, namely the use of antimicrobials and diarrhea, have a low predictive value for the diagnosis. AIM: To search other clinical variables and determine a clinical prediction model for (Clostridium difficile diarrhea. PATIENTS AND METHODS: All patients to whom a Clostridium difficile study was requested, were prospectively studied during 5 months. Clinical variables of these patients were registered. The diagnosis of Clostridium difficile was done using the cytotoxicity test in fibroblast cultures. RESULTS: Ninety two patients were analyzed and in 26, the diagnosis of Clostridium difficile was confirmed. A logistic regression model disclosed an age over 60 years old, the presence of mucus in the stools and a temperature over 37.8 degrees C in the previous 24 h, as significant predictors of the infection. The correlation of the model, between the predicted probability and the observed condition, was 81.5%. CONCLUSIONS: The presence of the clinical variables identified in this study are associated with a high probability of an infection by Clostridium difficile in patients with diarrhea and the recent use of antimicrobials.

Aged↗
PubMed2000

[Infective endocarditis: short and long-term results in 261 cases managed by a multidisciplinary approach].

BACKGROUND: Early diagnosis, an effective treatment and prompt recognition of complications are essential to improve the prognosis of infective endocarditis (IE). AIM: To report the results of a multidisciplinary approach to diagnosis and management of patients with IE at the Universidad Católica de Chile Hospital. PATIENTS AND METHODS: The clinical history, diagnosis, treatment and outcome of 261 episodes (Duke criteria) of IE admitted between January 1980 and January 1999 were analyzed. These included 185 episodes of native, 73 of prosthetic valve and 3 of nonvalvular IE. RESULTS: Sixty nine percent of patients were men and the mean age was 49 +/- 16 years. Seventy five percent had a definite diagnosis of IE (Duke). S. viridans, staphylococci and enterococci together constituted 85% of the isolated bacterial strains. Twenty seven had culture-negative IE, related to a high incidence of antibiotic therapy prior to diagnosis. Transesophageal echocardiography was performed in 102 cases and it detected vegetations in 91% of aortic and 96% of mitral IE, rupture or prosthesis dehiscence in 67% of aortic and 52% of mitral IE and abscesses in 51% of aortic and 15% of mitral IE. Fifty one percent developed heart failure and 34% had embolic events. S. aureus IE was associated to a higher incidence of embolic events, complications which contraindicated surgery and increased mortality rate (27%). Of all patients, 40% were treated exclusively with antibiotics, 52% were operated on and 8% had surgical indication but were nonoperable because of serious complications. The overall mortality was 16.3%: 13% in the medical, 9% in the surgical and 81% in the non-operable groups. The type of treatment and mortality rates did not differ between IE of native valves and prosthetic valves. Long term follow up showed survival rates of 73% at 5 years and 66% at 10 years. CONCLUSION: A multidisciplinary approach may be very helpful to improve the prognosis of IE.

Adolescent↗
PubMed1999

Adverse drug reactions (ADRs) in patients with HIV infection. A prospective study.

AIM: A prospective drug surveillance method was used to monitor 50 ambulatory patients with HIV infection, who were controlled in the Sexual Transmission Disease Service at Dr. Sotero del Río Hospital (Santiago, Chile). The aim of this work was to characterize and study the frequency, characteristics, and associated factors of the ADRs in HIV-infected patients. PATIENTS AND METHODS: Patients were interrogated once or twice a month by a clinical pharmacist, who consigned data concerning the drug prescribed by the physician, drug-related signs and symptoms, and the laboratory's parameters as renal, hepatic, hematological function, and biochemical test. The ADR probability was assessed for an algorithm. RESULTS: The frequency of adverse drug reactions found in the group of patients studied was 32.0%. The dermatological, hepatic, and hematological systems were the most affected by adverse drug reactions. Trimethroprim-sulfamethoxazole and zidovudine were the drugs mainly associated with ADRs. Patients with lymphocytes CD4+ count of 200 or less, presented a higher frequency of ADRs. 48.5% of ADRs were classified as probable. Severe reactions were found in 18.5% of the patients, and moderate in 70.4%. 50% of patients with ADRs needed the withdrawal of the implicated drug, and an 18.5% dose decreased. 63% of the ADRs were dose-independent. CONCLUSION: There was a higher frequency of ADRs in those patients with multiple-drug therapy, but the frequency of ADR was not associated with age, gender, or hematological test.

Anti-Infective Agents↗
PubMed1998

Time course of antibody response to tetanus toxoid and pneumococcal capsular polysaccharides in patients infected with HIV.

The temporal course of the humoral immune response to T-cell-dependent and T-cell-independent type 2 antigens was evaluated in HIV-infected patients. In all, 26 seropositive patients were vaccinated with tetanus toxoid and 23-valent pneumococcal vaccines; total IgG and IgG1 antibodies to tetanus toxoid (Ttox) and total IgG and IgG2 antibodies against 23 Streptococcus pneumoniae capsular antigens (PPS) were measured at baseline, 2 months, and 12 months after vaccination. For the Ttox, baseline levels of IgG1 (Ttox-IgG1) increased from 11.0 to 19.5 mg/L at 2 months postimmunization. Overall only 6 patients (23%) showed a significant response. At 12 months postvaccination, Ttox-IgG and T-tox-IgG1 were significantly lower than baseline levels (Ttox IgG basal; 11.0 mg/L, 12 months; 0.8 mg/L, Ttox IgG1 baseline; 13.1 mg/L, Ttox IgG1 12 months; 2.4 mg/L) and in 10 patients, antibodies that fell below protective levels (0.6 mg/L). In contrast with PPS, a significant response was observed at 2 and 12 months (PPS-IgG basal; 35.9 U/ml, 2 months; 151.4 U/ml, 12 months; 59.7 U/ml; PPS-IgG2 baseline 20.3 U/ml, 2 months; 113.2 U/ml, 12 months; 51.9 U/ml). Overall, 19 patients (76%) showed an immune response to pneumococcal polysaccharides antigens. Immunization with the Ttox T-cell-dependent antigen fails to elicit a significant immune response and may induce inhibition of antibody production in HIV-infected patients. In contrast, immunization with a T-cell-independent type 2 antigen can cause the pneumococcal polysaccharides to induce significant immune response in a high proportion of HIV-infected patients.

Adult↗
PubMed1998

[Resistance of human immunodeficiency virus (HIV) to zidovudine. Genotypic analysis in strains isolated from Chilean patients].

BACKGROUND: Resistance of HIV to AZT is the result of mutations in the pol gene that codifies the enzyme reverse transcriptase. AIM: To assess the resistance to antiretroviral drugs in Chilean patients infected with HIV. MATERIAL AND METHODS: The presence of mutations was searched in 22 patients infected with HIV. The emergence or persistence of these mutations was studied in sequential samples of 19 patients. The presence of the mutation that confers resistance to didanosine (DDI) was studied in those subjects exposed to the drug. Polymerase chain reaction techniques were used to analyze mutations in codons 41, 70 and 215 of the pol gene (resistance to AZT) and the mutation in codon 71 (resistance to DDI). RESULTS: On admission, none of the patients without previous exposure to AZT had drug resistance mutations. Seven of 12 patients (58.3%) that had received AZT had mutations in codon 215. In two, they were associated to a mutation in codon 41 and in two, a mutation in codon 70. After a mean follow up of 14 months, 13 of 15 patients (86%) that received AZT had viral strains genotypically resistant to the drug. In nine of these, the resistance was associated with disease progression. None of the 10 patients that received DDI had the mutation in codon 74 that confers resistance to the drug. However, in one of these patients, that never received AZT, a virus with a mutation in codon 215 was detected. CONCLUSIONS: A high percentage of patients that have received monotherapy with AZT have genotypic resistance to the drug. This resistance is associated with clinical and immunological derangement in 70% of these subjects.

Anti-HIV Agents↗
PubMed1996

Pharmacokinetics of vancomycin in patients with severely impaired renal function.

The pharmacokinetics of 1 g dose of intravenous vancomycin was studied in 8 patients with severe renal failure. Serum vancomycin levels were determined by fluorescence polarization immunoassay. After single dose of vancomycin peak concentrations ranged from 37.8 microg.ml-1 to 109.3 microg.ml-1 (mean 64.9 +/- 21.7 microg.ml-1). Vancomycin trough concentration 168h after administration of the antibiotic ranged from 2.23 microg.ml-1 to 11.42 microg.ml-1 (mean 6.55 +/- 2.8 microg.ml-1). The data were analyzed using a PCNONLINE computer program, and in all patients a triexponential model described how concentrations decreased in time. Three-compartment parameters obtained from the 8 patients were t1/2 alpha = 0.312 +/- 0.242 h, t1/2 beta 6.012 +/- 5.36 h, and t1/2 gamma = 131.0 +/- 46.7 h. Vd = 0.158 +/- 0.121 1.kg-1, Vdss = 0.920 +/- 0.248 1.kg-1 and total Cl = 0.10 +/- 0.049 1.h-1 per kg of weight. Between 1.5% and 21.2% of the administered vancomycin dose was eliminated during hemodialysis. The dialysis clearance of vancomycin ranged from 50.6 ml.min-1 to 76.8 ml.min-1 (average: 62.4 +/- 10.4 ml.min-1. However, after dialysis plasma concentrations returned to pre-dialysis values. In accordance to our kinetic study 1 g of vancomycin given every 7 days is adequate treatment for methicillin-resistant Staphylococcus aureus infections in patients with severe renal failure whose creatinine clearance is lower than 10 ml.min-1.

Adult↗
PubMed1996

[Natural history of human immunodeficiency virus infection in a cohort of Chilean patients].

We characterized clinical manifestations and the risk to develop AIDS in a cohort of 32 patients infected with human immunodeficiency virus without AIDS A multivariate analysis was performed to determine association between the progression of infection and control variables (socioeconomic level, age, sex and sexual preferences) and causal variables (psycho-social changes, significant clinical events, stress scoring and sexual activity). The cumulative AIDS incidence, defined as a CD4 lymphocyte count below 200 cells/cm3 was 50% at 6.5 years and 82% at 8 years. Using clinical criteria to define AIDS, 50% developed the disease at 8 years of follow up. Among studied factors, only age (faster progression at higher age) and time of evolution were associated with progression in stages before AIDS, the most frequent diseases were acute diarrhea, sexual transmission diseases, oral candidiasis, sinusitis and varicella zoster infections. The reduction; of CD4 lymphocytes-below 200 cells/cm3 always preceded the symptoms of the disease. Two patients have remained more than eight years without clinical or immunological deterioration.

Acquired Immunodeficiency Syndrome↗
PubMed1995

[Imipenem/cilastatin versus ceftazidime-amikacin in the treatment of febrile neutropenic patients].

AIM: To compare the efficacy of imipenem/cilastatine and ceftazidime-amikacin in the treatment of febrile neutropenic patients. DESIGN: Open, prospective and randomized clinical study. PATIENTS: Fifty two patients (26 female) aged 16 to 80 years old with 60 episodes of neutropenia were studied. They were randomly assigned to receive imipenem/cilastatine in doses of 500 mg iv qid or the combination of ceftazidime 1 to 1.5 g iv tid and amikacin 7.5 mg/kg iv bid. RESULTS: Global response to initial therapy was 53% in patients receiving imipenem/cilastatine and 37% in those receiving ceftazidime-amikacin (p = ns). When other antimicrobial were added, a 90 and 85% infection eradication success was achieved respectively. Six febrile episodes in the group receiving imipenem/cilastatine and 12 episodes in the group receiving ceftazidime-amikacin had Gram positive cocci as the sole infectious agent (p < 0.04). A lower duration of neutropenia had a favorable influence on treatment outcome. Three patients receiving imipenem/cilastatine (10%) and four receiving ceftazidime-amikacin (13%) died. Superinfections and toxicity related to antibiotics were minimal in both groups. CONCLUSIONS: Imipenem/cilastatine and the combination of ceftazidime with amikacin were equally effective in the treatment of febrile episodes in neutropenic patients.

Adolescent↗
PubMed1994

[Pneumonia caused by Pneumocystis carinii in immunodepressed patients: clinical picture, treatment, and prognosis].

Pneumocystis carinii pneumonia is frequent in patients with cellular immunity impairments, specially those with AIDS. We communicate our experience in 20 patients (15 with AIDS) with Pneumocystis carinii pneumonia confirmed by the finding of trophozoites or cysts. Clinical manifestations were cough in 75% of cases, dyspnea in 70% and fever in 65%. Eighty five percent of cases had diffuse reticular and nodular radiological densities. Nineteen patients had an increased alveolar-arterial O2 gradient. Nineteen patients were treated with trimethropim-sulphamethoxazole (TMP-SMX) and 4 with pentamidine isethionate (1 due to previous allergy and 3 due to poor response to TMP-SMX). Three patients died during the acute episode. Of the survivors, 13 died within 2 to 44 months later (14.5 +/- 12 months). It is concluded that AIDS is the most frequent underlying condition in patients with Pneumocysts carinii pneumonia and that long term survival is low.

AIDS-Related Opportunistic Infections↗
PubMed1993

Successful treatment of Trypanosoma cruzi encephalitis in a patient with hemophilia and AIDS.

Although the frequency of infection with the human immunodeficiency virus (HIV) is increasing dramatically in areas where Trypanosoma cruzi is endemic, trypanosomiasis has been rarely reported in persons with HIV infection or AIDS. Persons with hemophilia who receive multiple blood product transfusions from blood banks with little or no screening for infectious agents are at particularly high risk for infections with both HIV and T. cruzi. We describe the case of a person with hemophilia who was infected by blood transfusion with HIV and T. cruzi and in whom a multifocal, necrotic trypanosomal encephalitis was demonstrated by brain biopsy and electron microscopy. Treatment with benznidazole followed by that with itraconazole and fluconazole was associated with significant clinical and radiographic improvement.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Disseminated histoplasmosis in a patient with acquired immunodeficiency syndrome].

A twenty nine year old male homosexual presented with malaise, weight loss, fever and profuse sweating. An ill defined abdominal mass was found during physical examination in the right lower quadrant and chest X rays disclosed a pleural effusion. HIV antibodies and hepatitis B surface antigen were positive and immunological parameters were altered. Light and electron microscopic examination of operative biopsies of the abdominal mass revealed the presence of Histoplasma capsulatum. Treatment with Amphotericin B was started with a favorable response and the patient was discharged. He was readmitted with a septic shock and died. Necropsy showed pulmonary histoplasmosis. This is the first case of disseminated histoplasmosis in a patient with AIDS described in Chile.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Heparin-induced transaminase elevations: a prospective study.

An intensive and prospective surveillance study of 54 patients hospitalized in the Internal Medicine Unit of Clinical Hospital of the Catholic University of Chile, who required heparin in the period between June and December of 1991 was done. The aim of the work was to characterize and study the incidence of the adverse reactions associated with heparin therapy, with special emphasis on abnormal serum transaminase elevation. Abnormal transaminase elevation was defined as a rise over 20% of the serum transaminase baseline value. For determining the serum transaminase level, a UV spectrophotometric method was used. The incidence of the adverse drug reactions (ADR) was 24.1% (13 ADR), 8 of which (14.8%) were related with heparin therapy. Three of them (5.5%) corresponded to alanine transaminase (ALAT) increase and five (9.3%) to aspartate transaminase (ASAT) elevation. By means of global introspection method, 3 cases of ALAT increases were defined as probable and 6 as possible, while 5 ASAT increases were estimated as probable and 14 as possible. All of them were of slow onset, did not require treatment and hospital stay was not prolonged. Two patients' characteristics--age and sex--were associated with the development of heparin-induced abnormal alanine transaminase concentrations. The younger male patients showed a greater frequency of heparin-induced ALAT elevation. However, this association was not observed with the heparin-induced ASAT increase. These reactions were dose-dependent. Patients with heparin-induced ALAT elevation received a dose of 154,220 IU +/- 72,970 IU in comparison to patients without that adverse reaction who received 96,210 IU +/- 40,340 IU. This difference was statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Chagas disease with the acquired immunodeficiency syndrome. Clinical cases].

We report 2 patients with AIDS who developed Chagas infection, one with encephalitis, the other with acute myocarditis. The implications of immune depression for the manifestations and course of Chagas disease are discussed. Chagas disease should be considered in patients with AIDS who live in endemic zones and who develop cerebral or cardiac manifestations.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Acalculous acute cholecystitis caused by Cryptosporidium in a patient with AIDS].

We report a patient with the acquired immunodeficiency syndrome who developed acute cholecystitis. Removal of the gallbladder revealed infection by Cryptosporidium spp. The clinical course after cholecystectomy was favourable. The pathogenesis and therapy of this complication in patients with AIDS is discussed.

Acquired Immunodeficiency Syndrome↗