Predictors of psychosocial adaptation in children with CHD

Survival of CHD has significantly improved, but children with CHD remain susceptible to neurodevelopmental and psychosocial impairments. Our goal was to investigate the association between socio-demographic factors and psychosocial adaptation for future intervention. A retrospective cross-sectional study of an independent children's hospital's records was conducted. Psychosocial adaptation was measured by the Pediatric Cardiac Quality of Life Inventory Psychosocial Impact score (range 0-50, higher score indicates greater psychosocial adaptation). Bivariate and regression analyses were performed to estimate relationships between Psychosocial Impact score and socio-demographic variables including Child Opportunity Index, family support, financial support, academic support, and extracurricular activities. A total of 159 patients were included. Compared to patients in high opportunity neighbourhoods, patients in low opportunity neighbourhoods had a 9.27 (95% confidence interval [-17.15, -1.40], p = 0.021) point lower Psychosocial Impact score, whereas patients in moderate opportunity neighbourhoods had a 15.30 (95% confidence interval [-25.38, -5.22], p = 0.003) point lower Psychosocial Impact score. Compared to patients with adequate family support, those with limited support had a 6.23 point (95% confidence interval [-11.82, -0.643], p = 0.029) lower Psychosocial Impact score. Patients in moderate opportunity neighbourhoods had a higher Psychosocial Impact score by 11.80 (95% confidence interval [1.68, 21.91], p = 0.022) when they also had adequate family support compared to those with limited family support. Our findings indicate that among children with CHD, psychosocial adaptation is significantly impacted by neighbourhood resources and family support structures. These findings identify possible modifiable and protective factors to improve psychosocial adaptation in this vulnerable population.

Correlates between cardiovascular mortality and social determinants in Colombia, 2008 to 2017

Introduction

Cardiovascular disease is the leading cause of morbidity and mortality worldwide. In Colombia, a Latin-American country, cardiovascular disease accounts for nearly 30% of total deaths. The country has a high heterogeneity in social conditions, health services and ethnicity across the regions. Health is coverage by two main insurances as subsidized for the poor and contributive for formal workers.

Purpose

The aim of this study was to identify factors related with cardiovascular mortality

Methodology

A cross-sectional study using data from the official mortality registries of the National Administrative Department of Statistics of Colombia (DANE). Cardiovascular mortality was defined using the International Classification of Diseases 10 (ICD-10) I00–I09, I10–I15, I20–I25, I26–I45, I47–I49, I51, I46, I50, I60–I69, I70, I71–I99 and the corresponding ICD-9. Measures of frequency by region was estimated. Factors related to cardiovascular death were explored using a multilevel mixed-effects logistic regression.

Results

There were 2,073,275 deaths in Colombia between 2008 and 2017. 74.0% of them was due to noncommunicable diseases, 14.7% to injuries, and 11.2% to communicable, maternal, neonatal, and nutritional diseases. Of total 30.7% (636,987 deaths) were due to cardiovascular causes and 43.3% (897,502 deaths) to other non-communicable diseases. 29.6% of cardiovascular deaths were in people under 70 years of age. The highest proportion of premature deaths was in the San Andrés Island with 36.5%, following by the Orinoquía (34.8%), the Amazonía (34.1%) and the Caribe region (31.3%).

Male had higher cardiovascular mortality (OR=1.11, 95% CI: 1.10–1:12) related to women. Compared with people between 15 and 44 years of age, the chance of cardiovascular death increased in the categories of 45–70 years (OR=1.91, 95% CI: 1.87–1.95) and 70 years or older (OR=2.98, 95% CI: 2.92–3.04).

Those with African-Colombian ethnicity were more likely to die from cardiovascular disease (OR=1.13, 95% CI: 1.11–1.15) related to those without ethnic recognition and similarly the raizal ethnic group from San Andrés island, OR=1.35 (95% CI: 1.19–1.52). Illiteracy was related with a 32% (95% CI: 1.29–1.36) higher chance of cardiovascular death compared to having a professional degree. Those affiliated to subsidized were more likely to die from cardiovascular disease than those to the contributive insurance OR 1.26 (95% CI: 1.25–1.27)

Conclusion

Cardiovascular disease is the leading cause of death in Colombia with little reduction in the proportion of premature deaths over the period. Moreover, in the least wealthy regions the proportion was higher than the national average. Health inequalities was identified related to education, ethnic origin, and type of insurance. A region approach is needed to tackle the determinants of cardiovascular mortality.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The researcher David Rebellόn was supported by the Fogarty International Center of the National Institutes of Health under Award Number D43TW006589. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

The fibrinogen prothrombin time-derived method is not useful in patients anticoagulated with low molecular weight heparins or rivaroxaban

Essentials Fibrinogen prothrombin time-derived (FIBPT-d) behavior in anticoagulated patients is under studied. FIBPT-d method overestimates fibrinogen in rivaroxaban and low molecular weight heparin samples. Unfractionated heparin and dabigatran samples showed similar bias to the control group. Rabbit brain and human recombinant thromboplastin behavior was different in rivaroxaban samples.

SUMMARY

Background The fibrinogen prothrombin time-derived (FIBPT-d) method with photo-optical coagulometers is easy and economical. However, there are few reports on the behavior of this test on samples from patients anticoagulated with direct oral anticoagulants or low molecular weight heparin (LMWH). Objective To compare fibrinogen results obtained with the Clauss (FIB C) method and the FIBPT-d method with two thromboplastins in anticoagulated patients. Population The study population comprised 295 consecutive anticoagulated patients: 99 treated with vitamin K antagonists (VKAs), 49 treated with unfractionated heparin (UFH), 47 treated with LMWH, 50 treated with rivaroxaban, 50 treated with dabigatran, and 100 normal controls (NCs). Methods Dabigatran samples were analyzed by the use of FIB C with HemosIL Fibrinogen C or 100 NHI thrombin units mL-1 reagents; rabbit brain and human recombinant thromboplastins with HemosIL PTFibrinogen HS plus (HS) and Recombiplastin 2G (RP) were used for FIBPT-d method. Heparin and rivaroxaban levels were assessed with HemosIL Liq antiXa with specific calibrators; dabigatran levels were determined with the HemosIL Direct Thrombin Inhibitor Assay. All assays were performed on the ACL TOP platform in two laboratories. Percentage biases for the FIBPT-d method versus the FIB C method were calculated by the use of Bland-Altman plots. Results Positive biases of the FIBPT-d method versus the FIB C method with both thromboplastins were seen in NC samples (13.7% and 18.9% for HS and RP, respectively), but biases with HS in rivaroxaban and VKA patient samples were higher than that in NC samples, at 31.9% and 34.0%, respectively. LMWH patient samples showed higher bias than NC samples: 26.5% and 29.3.0% with HS and RP, respectively. UFH and dabigatran patient samples showed similar bias as NC samples. Conclusion The FIBPT-d method should not be used in anticoagulated patients, because the FIBPT-d mathematical algorithm has been validated only in normal subjects, so overestimation could occur in these patients.

Antitumor efficacy of mammalian target of rapamycin inhibitor therapy in liver transplant recipients with oncological disease: a case-control study

INTRODUCTION

The reported incidences of de novo malignancy following orthotopic liver transplantation (OLT) are significantly greater than those in the general population. We have analyzed the efficacy of mammalian target of rapamycin inhibitor (mTORi) as immunosuppressant therapy in patients with de novo malignancies or those engrafted because of a primary liver cancer.

METHODS

We performed a case-control study of patients with hepatocellular carcinoma (HCC; n = 119), cholangiocarcinoma (n = 1) or de novo malignancies (n = 73). Thirty-seven patients with these tumors were treated with mTORi, and 167, with calcineurin inhibitors (CNI). Switching to mTORi was performed progressively, withdrawing the CNI over 15 days, until obtaining levels of 5-10 ng/dL.

RESULTS

No incidence of rejection, serious adverse events, or death was observed with an overall actuarial survival of 68.5% in the mTORi group versus 45.7% among the CNI group. Overall rates of tumor recurrence were 15.2% and 36.8%, respectively (P < .05). Among patients with HCC, survival was 100% of mTORi with and 61.5% among CNI patients, with tumor recurrence rates of 6.2% and 19.1%, respectively (P < .05).

DISCUSSION

Surprising differences in survival and tumor recurrence rates were observed among the mTORi-treated group compared with controls. Switching from CNI to mTORi immunosuppressant therapy appeared to be safe. It seems to be reasonable to employ this strategy in liver transplant patients with primary hepatic or "de novo" neoplasms.

Rifampicin-resistant Mycobacterium tuberculosis: susceptibility to isoniazid and other anti-tuberculosis drugs

Based on data from 14 Supranational Tuberculosis (TB) Reference Laboratories worldwide, the proportion of rifampicin (RMP) resistant isolates that were isoniazid (INH) susceptible by phenotypic drug susceptibility testing varied widely (0.5-11.6%). RMP-resistant isolates that were INH-susceptible had significantly lower rates of resistance to other first- and second-line anti-tuberculosis drugs (except rifabutin) compared to multidrug-resistant isolates. RMP resistance is not always a good proxy for a presumptive diagnosis of multidrug-resistant TB, which has implications for use of molecular assays that identify only RMP resistance-associated DNA mutations.

Functionality of CD4+ and CD8+ T cells from tonsillar tissue

For many years, tonsillectomy has been used routinely in children to treat chronic or recurrent acute tonsillitis. Palatine tonsils are secondary lymphoid organs and the major barrier protecting the digestive and respiratory tracts from potential invasive microorganisms. They have been used as sources of lymphoid tissue; however, despite the hundreds of papers published on tonsillectomy, no studies addressing the functionality of the CD4(+) and CD8(+) T cells from chronically infected tonsils have yet been published. The aim of this study was to analyse the functionality of the CD4(+) and CD8(+) T cells with respect to tonsillar tissue. We used an affordable approach to measure the frequency of antigen-specific CD4(+) T cells, the direct ex-vivo cytotoxicity of CD8(+) T cells, memory T cell phenotype, cytokine profile and DC phenotype. Our results demonstrate that CD4(+) and CD8(+) T cells from tonsillar tissue are totally functional, as shown by their ability to produce cytokines, to degranulate and to differentiate into effector-memory T cells.

Liver transplantation in patients with cryptogenic cirrhosis: long-term follow-up

OBJECTIVE

The objective of this study was to evaluate long-term survival, histological diagnoses, and mobility of patients with cryptogenic cirrhosis (CC) treated with orthotopic liver transplantation (OLT).

PATIENTS AND METHODS

We performed a retrospective analysis of 35 patients who underwent transplantation with CC among 800 OLT patients. There were no differences in gender, mean age of 47 years, average MELD (Model for End-stage Liver Disease) of 16, and hepatocellular carcinoma incidence (8%).

RESULTS

In 28.6% of patients, the diagnosis of CC was wrong. There was no incidence of an acute rejection episode and a low incidence of complications, although the postoperative mortality rate was 20%, of chronic rejection was 25%, and recurrence of disease was 4%. Cumulative at 3-, 5-, and 10-year survivals were lower than the other OLT. Survival was lower in patients receiving suboptimal grafts.

CONCLUSIONS

One of 3 patients who underwent transplantation for CC had a specific etiologic diagnosis. The chronic rejection rate and postoperative mortality rate were higher than other etiologies, and survivals at 5, 10, and 15 years were lower than other OLT.

Efficacy and safety of non-operative management of blunt liver trauma

BACKGROUND

The liver is the most frequently affected organ during blunt abdominal trauma. Blunt liver trauma management has changed in the last two decades with the introduction of the computed tomography (CT) scan and non-operative management of stable patients.

OBJECTIVE

To determine the incidence, efficacy, and failure rate of blunt liver trauma non-operative management as well as the risk factors associated with such treatment in a level 1 trauma center in Colombia.

METHODS

We conducted an observational descriptive study on patients with blunt liver trauma who were admitted to a level 1 trauma center in Colombia. The evaluated outcomes were indications of immediate surgical treatment and the success of non-operative management.

RESULTS

A total of 73 patients were studied. The most common mechanism of trauma continues to be motor vehicle crashes. In 14 patients (19.2%), immediate surgical intervention was necessary and we observed a Revised Trauma Score (RTS) above 7.8 and intra-abdominal injuries as risk factors. Three patients died (21.4%). Fifty-nine patients (80.8%) received non-operative management, which failed in seven patients (11.2%). Age, severity of liver injury, and intra-abdominal injuries were not risk factors in the failure of non-operative management. Mortality in the non-operative management group was 1.7%.

CONCLUSION

Non-operative management is the treatment of choice for polytraumatized patients with blunt liver trauma who are hemodynamically stable. Non-operative management is an effective and safe treatment strategy. However, patients with an RTS score under 7.8 and other intra-abdominal non-liver injuries are at increased risk for an immediate surgical intervention.

Mucopolysaccharidosis type IVA (Morquio A disease): clinical review and current treatment

Mucopolysaccharidosis IVA (MPS IVA), also known as Morquio A, is a rare, autosomal recessive disorder caused by a deficiency of the lysosomal enzyme N-acetylgalatosamine-6-sulfate-sulfatase (GALNS), which catalyzes a step in the catabolism of glycosaminoglycans (GAGs), keratan sulfate (KS) and chondroitin-6-sulfate (C6S). It leads to accumulation of the KS and C6S, mainly in bone and cornea, causing a systemic skeletal chondrodysplasia. MPS IVA has a variable age of onset and variable rate of progression. Common presenting features include elevation of urinary and blood KS, marked short stature, hypoplasia of the odontoid process, pectus carinatum, kyphoscoliosis, genu valgum, laxity of joints and corneal clouding; however there is no central nervous system impairment. Generally, MPS IVA patients with a severe form do not survive beyond the third decade of life whereas those patients with an attenuated form may survive over 70 years. There has been no effective therapy for MPS IVA, and care has been palliative. Enzyme replacement therapy (ERT) and hematopoietic stem cell therapy (HSCT) have emerged as a treatment for mucopolysaccharidoses disorders, including Morquio A disease. This review provides an overview of the clinical manifestations, diagnosis and symptomatic management of patients with MPS IVA and describes potential perspectives of ERT and HSCT. The issue of treating very young patients is also discussed.

Observation of confined current ribbon in JET plasmas

We report the identification of a localized current structure inside the JET plasma. It is a field-aligned closed helical ribbon, carrying current in the same direction as the background current profile (cocurrent), rotating toroidally with the ion velocity (corotating). It appears to be located at a flat spot in the plasma pressure profile, at the top of the pedestal. The structure appears spontaneously in low density, high rotation plasmas, and can last up to 1.4 s, a time comparable to a local resistive time. It considerably delays the appearance of the first edge localized mode.

Efficacy, tolerance, and safety of mammalian target of rapamycin inhibitors as rescue immunosuppressants in liver transplantation

BACKGROUND

Mammalian target of rapamycin (mTOR) inhibitors behave as potent immunosuppressants which have the advantages, with respect to calcineurin inhibitors (CNI: cyclosporine or tacrolimus), of no nephrotoxicity and inhibition of cell proliferation. They are particularly suitable for patients with renal insufficiency or neoplasias.

MATERIALS AND METHODS

Twenty-two liver transplant patients were immunosuppressed with everolimus or sirolimus as rescue therapy after CNI treatment: 7 hepatocellular carcinomas; 5 de novo malignancies; 4 renal insufficiencies; 4 chronic rejections; and 2 acute rejection episodes.

RESULTS

There were 16.7% tumor recurrences, and 25% improvements in renal function, 75% in chronic rejection, and 50% in acute rejection. There was no incidence of rejection, kidney failure, gastrointestinal intolerance, hydrocarbon intolerance, hypertension, or arterial or venous thrombosis. We observed incidences of 50% for hypercholesterolemia, 31.8% for hypertriglyceridemia, 22.7% for thrombocytopenia, 18.2% for leukopenia, and 9.1% for anemia. The intercurrent infection rate was 13.6%, including oral thrush in 13.6%. Lower limb edema occurred in 13.6%, with 1 case of facial edema and 1 of alopecia.

CONCLUSIONS

mTOR inhibitors were safe immunosuppressive drugs whose side effects were controlled and easily managed. They have advantages with respect to CNI due to their slight effects on kidney function and lack of promotion of diabetes mellitus. Although their long-term effectiveness for control of neoplastic diseases is yet to be seen, they can be used safely in these patients with no incidence of rejection. Their effectiveness to control chronic rejection seems significant, but it is doubtful for steroid-resistant acute rejection episodes.

Morbidity and mortality in liver retransplantation

INTRODUCTION

The incidence of orthotopic liver retransplantation (re-OLT) ranges from 6% to 11%. The most frequent causes of early re-OLT are allograft failure, uncontrolled acute rejection, and vascular complications.

MATERIALS AND METHODS

A retrospective study of 512 orthotopic liver transplants (OLTs) in 482 patients over 15 years.

RESULTS

The incidence of re-OLT was 6.6%, with a higher percentage of men requiring re-OLT than first-time OLT (75.0% vs 63.0%, P < .05). The reasons for re-OLT were thrombosis 21.7%, aneurysm 6.5%, stenosis 3.2%, primary nonfunction (PNF) 21.7%, and chronic rejection or recurrence of the initial disease 40.4%. Complications included PNF (22.0%), acute renal failure (65.6%), postoperative infection (87.5%), and adult respiratory distress syndrome (9.4%; P < .05). No differences were seen in the incidence of septicemia or postoperative hemorrhage. The average survival was much lower in re-OLT (21.8 days) compared with OLT (194.5 days; P < .05). The mortality rates in re-OLT were 100% for primary biliary cirrhosis, 85.7% for HCV, 50% for alcoholic cirrhosis, and 20% for HBV. A direct association between the Model for End-stage Liver Disease (MELD) score and the number of complications was present.

DISCUSSION

There was a greater requirement for re-OLT in men and those patients transplanted due to hepatitis B virus cirrhosis and fulminant hepatitis (P < .05). The re-OLT patients had no greater incidence of sepsis compared with the OLT patients, although they did have a greater incidence of primary graft dysfunction, acute renal failure, adult respiratory distress syndrome, and postoperative infection (P < .05). The MELD was a good parameter for predicting graft evolution. Re-OLT in patients with primary biliary cirrhosis and hepatitis C virus was associated with a high degree of mortality.

Early postoperative response of cytokines in liver transplant recipients

We evaluated the early postoperative response of several cytokines (IL-2, IL-4, IL-6, IL-10, TNF-alpha, IFN-gamma) prior to liver transplantation (T(0)) as well as 1, 6, and 12 hours and 1, 2, 3, 5, and 7 days afterward. Cytokine concentrations were correlated with serum levels of bilirubin as a predictor of postoperative complications. Cytokine levels were determined in plasma samples from 16 liver transplant recipients (13 men, 3 women) aged 43 to 61 years. IL-6 and IL-10 reached their maximum concentrations 1 hour after transplantation. Each increase in IL-6 correlated to a rise in IL-10. IL-2, IL-4, TNF-alpha, and IFN-gamma had a particular time-course for each patient studied. Bilirubin fell to almost normal values but not in cases of postoperative complications, where IL-6 showed values four times higher compared to those of liver transplant recipients who did not show postoperative complications. IL-6 and IL-10 plasma concentrations and serum bilirubin level might be useful as a predictive factor of postoperative complications in liver transplant recipients.

Deep Impact: observations from a worldwide Earth-based campaign

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.

Multicenter study of MTT and resazurin assays for testing susceptibility to first-line anti-tuberculosis drugs

OBJECTIVE

A multicentre evaluation was performed to assess two rapid low-cost methods, MTT (3-[4.5-dimethylthiazol-2-yl]-2.5-diphenyltetrazolium bromide) and resazurin assays, for testing the susceptibility of Mycobacterium tuberculosis to the first-line anti-tuberculosis drugs rifampicin (RMP), isoniazid (INH), ethambutol (EMB) and streptomycin (SM).

METHODS

Thirty coded M. tuberculosis strains were sent to seven laboratories located in Latin America, representing six countries. Each site performed the colorimetric assays, MTT and resazurin, blind for the first-line drugs RMP, INH, EMB and SM. The minimum inhibitory concentration results obtained were compared to the conventional proportion method on Lowenstein-Jensen medium.

RESULTS

After establishing the breakpoint concentrations, excellent results were obtained for RMP, INH and EMB, with levels of specificity and sensitivity of between 96% and 99%.

CONCLUSION

MTT and resazurin assays are promising, accessible new alternative methods for middle- and low-resource countries that need low-cost methods to perform rapid susceptibility testing of M. tuberculosis to key anti-tuberculosis drugs.

A marked difference in pathogenesis and immune response induced by different Mycobacterium tuberculosis genotypes

In the last decade, an unprecedented genetic diversity has been disclosed among Mycobacterium tuberculosis strains found worldwide. However, well-conserved genotypes seem to prevail in areas with high incidence of tuberculosis. As this may be related to selective advantages, such as advanced mechanisms to circumvent [M. bovis Bacille Calmette-Guerin (BCG)-induced] host defence mechanisms, we investigated the influence of strain diversity on the course of experimental disease. Twelve M. tuberculosis strains, representing four major genotype families found worldwide today, and the laboratory strain H37Rv were each used to infect BALB/c mice by direct intratracheal injection. Compared with H37Rv, infections with Beijng strains were characterized by extensive pneumonia, early but ephemeral tumour necrosis factor-alpha (TNF-alpha) and inducible isoform of nitric oxide synthetase (iNOS) expression, and significantly higher earlier mortality. Conversely, Canetti strains induced limited pneumonia, sustained TNF-alpha and iNOS expression in lungs, and almost 100% survival. Strains of the Somali and the Haarlem genotype families displayed less homogeneous, intermediate rates of survival. Previous BCG vaccination protected less effectively against infection with Beijing strains than against the H37Rv strain. In conclusion, genetically different M. tuberculosis strains evoked markedly different immunopathological events. Bacteria with the Beijing genotype, highly prevalent in Asia and the former USSR, elicited a non-protective immune response in mice and were the most virulent. Future immunological research, particularly on candidate vaccines, should include a broad spectrum of M. tuberculosis genotypes rather than a few laboratory strains.

[False-positive cultures due to cross contamination in tuberculosis laboratories]

Fifteen episodes of Mycobacterium tuberculosis laboratory cross-contamination suspected between 1996 and 2001 at 6 laboratories in Buenos Aires City and suburbs were investigated by IS6110 RFLP. Thirteen episodes were confirmed. Even though BACTEC 460 produced the highest number of confirmed episodes in a single laboratory, the most extended one occurred while employing conventional culture procedures in solid medium. The double repetitive element-polymerase chain reaction (DRE-PCR) was applied to 8 of these episodes and produced concordant results with those of the RFLP. The DRE-PCR appears to be a valuable tool for the prompt identification of false positive cultures. The timely rectification of defects in laboratory protocols can avert false diagnoses of tuberculosis and unnecessary prolonged treatments.

[The Mycobacteria Growth Indicator Tube (MGIT) is useful for anticipating the resistance of Mycobacterium tuberculosis to rifampicin but not to isoniazid]

A previously proposed MGIT protocol was assessed focussing on its reliability to test the mainstay antituberculous drugs. Isoniazid (H) (0.1 mg/l) and rifampin (R) (1 mg/l) were assayed against 109 Mycobacterium tuberculosis isolates affecting patients at high risk of multidrug-resistant tuberculosis. All isolates were simultaneously tested on Löwenstein-Jensen medium by the proportion method considered the gold standard. MGIT readings were accomplished within 2 and 22 days after inoculation, at day 10, 93.4% of the tests were completed. Unsatisfactory to evaluate H activity, the assay misclassified 8.8% (5/57) H susceptible and 7.7% (4/52) H resistant isolates. Otherwise, it yielded correct results for all 60 R susceptible isolates and 93.9% (46/49) R resistant isolates. Properly backed-up by a conventional test and targeting high risk patients, the MGIT system proved to be a useful aid to anticipate most of resistance to R. Accuracy, cost and turnaround time were competitive compared with those of semi-automated culture-based or molecular methods.

[Diagnosis of tuberculosis in children in provinces of Argentina]

Confirming the diagnosis of pediatric tuberculosis is cumbersome, due to the clinical features (generally paucibacillary forms) of the disease. This national study was undertaken in order to establish: the features of childhood tuberculosis at the time of diagnosis, the criteria on which the pediatricians based the diagnosis, the bacteriologic contribution to the diagnosis and the quality of notifications to the National Programme. Medical and laboratory records were reviewed for children under 15 years of age who were diagnosed with tuberculosis disease or primary infection during 1995. The study included children cared for at health centres from Argentinean provinces (capital city excluded) where pediatricians accepted to participate. Four hundred cases (17% of childhood notifications to the National Programme) and 81 primary infections were studied. The percentage of children studied by means of chest radiology, presence of symptoms, Mantoux test, case contact investigation and bacteriology were 95.3%, 79.6%, 90.1%, 92.7% and 35% for pulmonary cases, respectively, and 87.7%, 100%, 87.7%, 85.9% and 78.9% for extra-pulmonary cases, respectively. Of the evaluated pulmonary cases, 99.1% had abnormal x-rays, 79.0% had a tuberculin test > or = 10 mm, 79.8% had symptoms and 80.2% had a history of close contact. All extra-pulmonary patients had symptoms at the time of diagnosis; 63.0% had abnormal chest radiograph at diagnosis. Bacteriologic confirmation was achieved in 10.7% of the cases (20.8% and 40.0% of the investigated pulmonary and extra-pulmonary cases, respectively). This study would indicate that the diagnosis is made at relatively early stages of the disease. In general, recommendations of the Argentine Society of Pediatrics were followed. A low rate of bacteriological proof of diagnosis was observed, probably due to the scarce bacteriologic investigation and the low yield achieved in culturing pulmonary specimens. The study found under-register of cases and lack of precision in the information reaching the National Programme.

[Tuberculosis focused through the molecular biology zoom]

The sequence of Mycobacterium tuberculosis genome set up a process of systematic research and improved the understanding of the microorganism biology, albeit the clues of its virulence and pathogenicity still remain rather cryptic. Genetic engineering did not succeed in designing more effective or convenient tools to accomplish the control of tuberculosis. Neither the bacillus variants created by mutagenesis and recombination nor the microorganism subunits (antigens, DNA) proved to be significantly better than the BCG vaccine as immunogens. Likewise, the search for novel bacterial targets and more active antibiotics has been unfruitful thus far, even though some advance in drugs formula or delivery systems is in progress. Conversely, new and ingenious instruments have been developed to optimize the epidemiological tracing and diagnosis of the disease. The finding of strain molecular markers consolidated the investigation of tuberculosis spread and revealed the expansion and prevalence of certain lineages of the bacillus in some ecological niches. Molecular methods are specific to immediately characterize the bacilli detected by microscopy or culture which resulted in rapid diagnosis build-up. This improvement is decisive for immunodepressed patients and those affected by multidrug-resistant tuberculosis. To be meaningful and precise the results produced by molecular investigations must be properly backed up by conventional microbiology, pathology and epidemiology.

[Resistance and multiresistance to antitubercular drugs in Argentina and in other Latin American countries]

Resistance of Mycobacterium tuberculosis to both isoniazid (INH) and rifampicin (RPM), the most important antituberculosis drugs, with or without simultaneous resistance to other drugs, is known as multidrug resistance (MDR). It is the main obstacle to attain the cure of patients by the specific treatment, and a threat to the tuberculosis control. Between 1994 and 1997, several Latin American countries undertook countrywide surveys or surveillance programs to determine their primary and acquired drug resistance prevalence rates. These studies followed the WHO/International Union Against Tuberculosis and Lung Diseases (IUATLD) guidelines. Percentages of not previously treated patients with tuberculosis due to MDR strains ranged from null or very small (Uruguay, Cuba, Chile) to 4% or higher (Dominican Republic, Argentina). In Argentina, a remarkable correlation between MDR tuberculosis, AIDS and the assistance in urban reference hospitals for infections diseases was observed. Coincidentally with the survey, nosocomial spread of HIV-related MDR tuberculosis occurred in two of these hospitals situated in Buenos Aires and Rosario. But, at the same time, an alarming emergence of MDR was evidenced among non HIV-infected patients with history of previous antituberculosis treatment. Directly observed treatment (DOT) should be increasingly applied, and drug supply guaranteed. Treatment as well as microscopy services for diagnosis and follow up of patients, should be decentralized from the big specialized hospitals in urban areas to the peripheral health centers, in order to make easier for the patients to attend regularly and receive their medications. These strategies will contribute to increase cure rates and to reduce the tuberculosis transmission.

Intra-articular analgesia after arthroscopic knee surgery: comparison of three different regimens

One hundred and three patients ASA grades I-II, 16-80 years of age scheduled for arthroscopic meniscectomy were prospectively studied, and randomly allocated to one of four groups: group 1 (n = 25): 0.25% bupivacaine (50 mg) intra-articular (IA), group 2 (n = 27): 1 mg of 0.1% preservative free morphine chloride in saline, group 3 (n = 26): 1 mg of 0.1% preservative free morphine chloride in 0.25% bupivacaine and group 4 (n = 25): normal saline (0.9%). The volume given was always 20 mL. Ketorolac [Toradol, 30 mg intramuscularly (i.m.)] was used as rescue medication; analgesia was assessed using a visual analogue scale (VAS), a verbal rating scale (VRS), supplemental analgesic consumption post-operatively (SAC) and the presence of side effects. Verbal rating scale and visual analogue scale scores showed better pain control in group 1, 20 min after surgery, and in groups 1 and 2 at 4 h and 10 h as well as in the global VAS. In multifactorial analysis no significant differences among groups or side effects was found, pH analysis of the substances used showed no alterations in the basal pH range. The analgesic efficacy of 20 mL of bupivacaine 0.25% is similar to that of 1 mg of morphine in 20 mL of saline 0.9%. The morphine-bupivacaine mixture was no more efficacious than bupivacaine or morphine alone.

A single, double lumen high-flow catheter for patients undergoing peripheral blood stem cell transplantation. Experience at the National Cancer Institute in Mexico

Peripheral blood stem cell transplantation (PBSCT) requires a high-flow catheter for adequate cell collection by apheresis and long i.v. support, this is usually achieved by multiple catheters. We analyzed our experience with Mahurkar or Permacath for apheresis and long-term i.v. support in PBSCT, cared for exclusively by an i.v. therapy team. Fifty-six catheters were used in 53 patients that completed PBSCT (28 Permacath and 28 Mahurkar). In 10 patients (19%) the same catheter was used for multiple PBSCT. The average stay was 58.4 days (7-219), Permacath 76.8 days (14-219) and Mahurkar 42 days (7-106). The incidence of infectious complications was 2.2 x 1000 catheter-days (1.7 Permacath and 3.0 Mahurkar); during neutropenia it was 3.7 x 1000 cathether-days. The incidence of thrombosis was 0.9 x 1000 catheter-days. There was a total of seven infectious episodes (12.7%). Five (9%) were local and two were (3.6%) bacteremias. The microorganism most commonly isolated was Staphylococcus sp. (57%). Four catheters (7.1%) were removed because of complications: one thrombosis and three infections. Both catheters have proven useful and safe for long-lasting vascular access in patients undergoing PBSCT. No statistical difference was found in infectious and non-infectious complications between either catheters.

Nosocomial spread of human immunodeficiency virus-related multidrug-resistant tuberculosis in Buenos Aires

A steep upsurge of human immunodeficiency virus (HIV)-associated multidrug-resistant tuberculosis (MDR-TB) was recently observed at a referral treatment center in Buenos Aires City. Between January 1994 and June 1995, TB isolates resistant to at least five drugs were recovered from 101 of 272 HIV-infected inpatients. Highly resistant isolates from 77 patients underwent restriction fragment length polymorphism study with IS6110. After cross-contamination was eliminated, a single TB strain was found to have caused disease in 68 patients with a history of on-site exposure. The frequency of smear-positive pulmonary disease was higher among these patients than among non-MDR-TB HIV-infected patients (50/68 vs. 60/148, P < .001), and the 1-year survival was dramatically reduced (5/68 vs. 92/148). The strain involved in the outbreak was traced back to patients hospitalized in 1992. Institutional infection control policies were and may still be inadequate to contain the spread of TB among immunodepressed subjects, as is the case in other large urban hospitals in Argentina.

A comparative study of analgesia after knee surgery with intraarticular bupivacaine, intraarticular morphine, and lumbar plexus block

Following arthroscopic surgery of the knee, 60 ASA I-II patients were randomly allocated to three different groups (n = 20 each) in an attempt to establish the best postoperative analgesic protocol: 20 ml of bupivacaine (0.25%; 50 mg) intra-articularly (IA) (Group 1); continuous three-in-one lumbar plexus block using a catheter to administer 0.25 ml/kg of bupivacaine (0.25%; single-shot) plus continuous pump infusion of the same drug (0.03 ml.kg-1 x h-1 of 0.25% bupivacaine for 24 h) (Group 2); or 1 mg of morphine with 20 ml of saline IA (Group 3). The results were appraised in a double-blind manner, and the degree of postoperative pain was evaluated by visual analog scale (VAS) at constant hourly intervals for the first 24 h, by the incidence of secondary effects, and by the need for complementary analgesia. Group 2 (three-in-one) VAS values were lower 16 and 24 h after surgery and also globally (P < 0.05), with respect to the other two groups. Five patients in Groups 1 and 3 required complementary analgesia, while three patients in Group 1 suffered nausea. No other secondary effects were observed. We conclude that all three analgesic methods proved efficient, as reflected by the scant requirements for additional analgesics and the degree of expressed patient satisfaction. However, lumbar plexus block (three-in-one) with continuous bupivacaine infusion was most effective, and, although it constitutes an added technique, its scant complications and easy performance make its use advisable.

Humoral response to Mycobacterium tuberculosis in patients with human immunodeficiency virus infection

The effect of the human immunodeficiency virus (HIV) on mycobacterial antibody production was investigated. Using an enzyme-linked immunosorbent assay (ELISA) for detecting IgG against Mycobacterium tuberculosis PPD, it was observed that individuals at risk of HIV infection show a pattern of humoral response to the tubercle bacillus similar to that previously found in the immunocompetent population not exposed to risk factors: 6 of 12 (50.0%) tuberculosis cases had elevated levels of antibodies to PPD and 27 of 30 (90.0%) asymptomatic individuals had antibody levels within the normal range. In an HIV-seropositive group without AIDS indicator diseases, 8 of 22 (36.4%) tuberculous patients had detectable mycobacterial antibodies whereas 156 of 164 (95.1%) non-tuberculous subjects did not. Among AIDS cases, only 1 of 20 (5.0%) patients with tuberculosis and none of 53 non-tuberculous subjects showed a positive result. The study evidenced an increasing humoral unresponsiveness to PPD in the progression of HIV infection to AIDS. Thus, a serodiagnostic method for detecting tuberculosis such as the ELISA here employed noticeably decreases its utility in the latency stage of the HIV infection, and it is practically useless in clinical AIDS.

Evaluation of synthetic pseudo cord-factor-like glycolipids for the serodiagnosis of tuberculosis

A number of glycolipids were evaluated in an ELISA test for their serodiagnostic usefulness in tuberculosis. One hundred and twelve (112) sera belonging to bacteriologically confirmed TB patients, patients with pathologies other than tuberculosis and healthy individuals were examined against several synthetic "mirror" pseudo cord factors (analogues of trehalose-6,6'-dimycolate or TDM) using natural cord factor and another recently described natural glycolipid (SL-IV) of Mycobacterium tuberculosis as control antigens. Analysis of the results shows that all synthetic "mirror" pseudo cord factors, except one with a short 8-carbon chain, were better recognized by the sera of tuberculosis patients than natural cord factor, with sensitivity and specificity values in the ELISA test similar to those reported for M. tuberculosis species-specific SL-IV. Of all antigens tested in this study, BDA. TDA, a bis(N,N-dioctadecylamide) of "trehalose dicarboxylic acid", [(alpha-D-glucopyranosyluronic acid) (alpha-D-glucopyranosiduranic acid)], showed the highest serodiagnostic discriminating power (93% sensitivity and specificity). We postulate that either these artificial molecules are cross-reactants of similarly structured native glycolipids of M. tuberculosis or that they bear closer resemblance to actual phagosome-lysosome-modified antigens than to native mycobacterial ones.

Genetic resistance/susceptibility to mycobacteria: phenotypic expression in bone marrow derived macrophage lines

Congenic strains of mice susceptible (B10A.Bcgs) or resistant (B10A.Bcgr) to BCG were established. Here we describe the model system which has been established to analyze the functional activities of macrophages in the two strains. We have immortalized bone marrow macrophages from B10A.Bcgs and B10A.Bcgr congenic strains of mice and derived cloned macrophage lines designated B10S and B10R, respectively. B10R and B10S cell lines exhibited surface markers and morphology typical of macrophages. B10S and B10R were similar in their phagocytic activity, in their level of c-fms, in their transforming growth factor beta (TGF beta) mRNAs expression, and in their expression of tumoricidal activity in response to interferon-gamma (IFN gamma) plus lipopolysaccharides (LPS). However, B10R macrophages expressed a higher level of la mRNA when activated with IFN gamma compared with B10S macrophages. Analysis of the bacteriostatic activity of the two cell lines revealed that B10R macrophages were much more active in inhibiting Mycobacterium smegmatis replication than B10S. To measure the intracellular destruction of bacilli, a bactericidal assay based on hybridization with an oligonucleotide probe specific for mycobacterial ribosomal RNA was designed. The results demonstrated that B10R macrophages were endowed with enhanced constitutive bactericidal activity as compared with B10S. In conclusion we have obtained macrophage lines from bone marrow of B10A.Bcgs and B10A.Bcgr mice that express to a similar extent functional and phenotypic characteristics of macrophages. However, we demonstrate that relative to B10S macrophages, the B10R macrophages have higher expression of la mRNA and that they are constitutively more active in expressing mycobactericidal activity.

[Usefulness of the enzyme immunoassay in the diagnosis of tuberculosis]

To assess the usefulness of enzyme immunoassay as a rapid method of diagnosing tuberculosis, a study was conducted of 687 serum samples from 271 children and 416 adults. With 55 sera from nontuberculous children as controls, the specificity was 0.98, and with 137 controls from the adult population, 0.93. Prior vaccination with BCG did not influence the level of detectable anti-PPD antibody. The results were similar in healthy PPD-positive and negative adults. The test differentiated mycoses and nontuberculous mycobacterioses from tuberculosis. The sensitivity rates in 49 children and 200 adults diagnosed with bacteriologically confirmed pulmonary and extrapulmonary tuberculosis were calculated at 0.51 and 0.69, respectively. In those tuberculosis cases not bacteriologically confirmed or at other sites, the test was positive in 28.1% of 114 children and in 48.6% of 35 adults. The cost, speed, and availability of reagents for this test were comparable to those for direct microscopic examination. Both methods were positive for 49% of the tuberculosis cases confirmed by culture, and a total of 84% of those cases were found positive using one method or the other. It is concluded that enzyme immunoassay can be especially useful in the rapid diagnosis of nonbacilliferous pulmonary, extrapulmonary, and childhood tuberculosis.

Reciprocal cellular and humoral immune responses in bovine tuberculosis

A sandwich ELISA for the detection of gamma interferon showed higher sensitivity and specificity than an indirect ELISA for mycobacterial antibodies in the diagnosis of bovine tuberculosis. Circumstantial evidence of an inverse relationship between cellular and humoral immune responses to Mycobacterium bovis was found in cattle with natural infection.

Further evaluation of an indirect enzyme-linked immunosorbent assay for the diagnosis of bovine tuberculosis

The sensitivity and specificity of an ELISA for the detection of bovine IgG anti-Mycobacterium bovis antibodies were 73.6% and 94.1%, respectively, as determined in 53 bacteriologically confirmed tuberculous cattle and 101 healthy cattle from a tuberculosis-free area. In addition, the results of ELISA and tuberculin tests in 149 cattle were compared with those of subsequent necropsy studies. Both tests failed to detect 2 animals with tuberculous lesions and positive culture; 3/12 cattle with M. bovis isolation and no lesions, and 2/7 with atypical mycobacterial infection reacted to tuberculin, but none had antibodies; in 128 cattle with neither lesions nor mycobacterial isolation, 6 were tuberculin reactors and 7 others had antibodies. Negative results were obtained by ELISA in 21/22 paratuberculous cattle. Antibodies were not detected in 88.9% to 96.4% of 697 cattle from two tuberculin negative herds of an endemic area. In a herd with proved M. bovis infection, distribution of seropositive animals in tuberculin and non-tuberculin reactors was similar. Antibody responses to cutaneous tuberculin stimuli were observed in 4 experimentally infected cattle, but only in 2/10 healthy controls after repeated PPD stimuli. Nine controls which had either received a single tuberculin dose or none showed no increase in antibody levels. The low sensitivity of this ELISA limits its usefulness as a diagnostic tool for bovine tuberculosis eradication campaigns. However, it could be helpful in epidemiological surveillance if its efficiency to identify infected herds is demonstrated.

Detection of circulating antibodies to purified protein derivative by enzyme-linked immunosorbent assay: its potential for the rapid diagnosis of tuberculosis

An enzyme-linked immunosorbent assay for detecting antibodies to purified protein derivative was evaluated as a rapid method for serodiagnosis of childhood tuberculosis. Its specificity for IgG antibodies was 0.98 as determined in 55 sera from nontuberculous children who showed no significant effect of previous Bacillus Calmette-Guérin vaccination on the production of specific antibodies. Results were negative in 29 of 33 (87.9%) tuberculin-positive children and in 18 of 20 (90.0%) contacts, none of whom had evidence of tuberculosis. The sensitivity of this test was 0.51 as determined in 49 sera from bacteriologically confirmed cases; 17 of 27 smear positive cases and 8 of 22 children with positive cultures were detected. Results were positive in 32 of 114 (28.1%) patients with a diagnosis of tuberculosis not confirmed by microbiology. Consequently whereas a negative result does not rule out tuberculosis, a positive result is a strong indication of the disease. The IgM antibody determination yielded much less discriminative results.

[Evaluation of four antigens for the detection of anti-Mycobacterium bovis antibodies by enzyme immunoassay]

An enzyme-linked immunosorbent assay (ELISA) for the diagnosis of bovine tuberculosis through the detection of specific seric antibodies has recently been developed in our laboratory. In order to assess its reproducibility and select the most adequate antigen, four bovine PPDs from different sources were evaluated in parallel: PPD M. bovis strain AN5, CEPANZO standard (CPZ), PPD M. bovis strain AN5, European Economic Community standard (EEC), PPD M. bovis strain AN5, prepared from non heated bacilli, killed by phenol (P) and PPD. M. bovis BCG strain prepared at the Pasteur Institute, Paris (BCG). Sera from 22 healthy cattle from tuberculosis free area and 20 bacteriologically confirmed tuberculous animals were employed in simultaneous assays. Antibody mean and standard deviations from healthy cattle expressed as optical density (OD) values were 45 +/- 22 when CPZ was used as antigen, 24 +/- 10 with EEC, 103 +/- 56 with P and 56 +/- 20 with BCG. Mean O.D. from tuberculous cattle were 588 +/- 158, 510 +/- 234, 782 +/- 138 and 441 +/- 189 with antigens CPZ, EEC, P and BCG respectively. A close correlation was observed when results obtained with EEC and P were compared with that of CPZ (r: 0.97 and 0.94 respectively). A lower specificity was achieved when BCG was used as antigen being also lower its correlation with the results obtained with CPZ (r: 0.87). It is concluded that our ELISA would achieve similar sensitivity and specificity if CPZ, EEC and P were used as antigens. On the other hand, BCG would not be suitable for this assay.

Nontuberculous mycobacteria and Mycobacterium bovis as a cause of human disease in Argentina

Fifteen laboratories from six regions of the country participated in the present trial covering the three years period 1982-84 during which they obtained 13544 mycobacterial cultures from 7672 patients. Of the total isolates, 437 (3.22%) were nontuberculous mycobacteria and 49 (0.36%) Mycobacterium bovis. The remaining cultures were identified as M. tuberculosis, which was the infectious agent in 7609 cases (99.17%). A further 36 cases (0.47%) were due to M. bovis and the remaining 27 to nontuberculous mycobacteria (0.35%). This last group included 26 cases due to M. avium - intracellulare - scrofulaceum complex (MAIS) and one due to M. chelonae. All these were cases in adults with pulmonary lesions except for a lymphadenitis diagnosed in a child. According to these results, the frequency of bovine tuberculosis is low in Argentina. Most of these cases were found in rural and slaughterhouse workers. Non tuberculous mycobacterioses are also of low frequency in the country.