Diagnóstico por imagen de las metástasis vertebrales / Imaging diagnosis of vertebral metastasis

La columna vertebral es la tercera ubicación más frecuente para la enfermedad metastásica, después del pulmón y el hígado. Por otra parte, los tumores óseos más recurrentes son las metástasis, siendo la columna su principal lugar de localización. En este trabajo se realiza una revisión de las diferentes técnicas de imagen disponibles, tanto radiológicas como de medicina nuclear, y de la apariencia morfológica de las metástasis de columna en cada una de ellas. La resonancia magnética (RM) es la mejor modalidad de imagen para la detección de metástasis en la columna. Es importante efectuar el diagnóstico diferencial entre fractura vertebral de causa osteoporótica y patológica. La compresión medular es una complicación grave de la enfermedad metastásica y su valoración mediante imagen a través de escalas objetivas es determinante para la estimación de la estabilidad de la columna y, por consiguiente, para establecer el tratamiento. Por último, se comentan brevemente las técnicas de intervencionismo percutáneo.(AU)

The spine is the third most frequent location for metastatic disease, after the lung and liver. On the other hand, the most frequent bone tumors are metastases and the spine is the main location. A review of the different imaging techniques available, both radiological and nuclear medicine, and the morphological appearance of spinal metastases in each of them is performed. Magnetic resonance imaging is the best imaging modality for detection of spinal metastases. It is important to make the differential diagnosis between vertebral fracture of osteoporotic and pathological cause. Spinal cord compression is a serious complication of metastatic disease and its assessment by imaging through objective scales is decisive for estimating spinal stability and therefore establishing treatment. Lastly, percutaneous intervention techniques are briefly discussed.(AU)

[Translated article] Imaging diagnosis of vertebral metastasis / Diagnóstico por imagen de las metástasis vertebrales

La columna vertebral es la tercera ubicación más frecuente para la enfermedad metastásica, después del pulmón y el hígado. Por otra parte, los tumores óseos más recurrentes son las metástasis, siendo la columna su principal lugar de localización. En este trabajo se realiza una revisión de las diferentes técnicas de imagen disponibles, tanto radiológicas como de medicina nuclear, y de la apariencia morfológica de las metástasis de columna en cada una de ellas. La resonancia magnética (RM) es la mejor modalidad de imagen para la detección de metástasis en la columna. Es importante efectuar el diagnóstico diferencial entre fractura vertebral de causa osteoporótica y patológica. La compresión medular es una complicación grave de la enfermedad metastásica y su valoración mediante imagen a través de escalas objetivas es determinante para la estimación de la estabilidad de la columna y, por consiguiente, para establecer el tratamiento. Por último, se comentan brevemente las técnicas de intervencionismo percutáneo.(AU)

The spine is the third most frequent location for metastatic disease, after the lung and liver. On the other hand, the most frequent bone tumors are metastases and the spine is the main location. A review of the different imaging techniques available, both radiological and nuclear medicine, and the morphological appearance of spinal metastases in each of them is performed. Magnetic resonance imaging is the best imaging modality for detection of spinal metastases. It is important to make the differential diagnosis between vertebral fracture of osteoporotic and pathological cause. Spinal cord compression is a serious complication of metastatic disease and its assessment by imaging through objective scales is decisive for estimating spinal stability and therefore establishing treatment. Lastly, percutaneous intervention techniques are briefly discussed.(AU)

[Translated article] Imaging diagnosis of vertebral metastasis.

The spine is the third most frequent location for metastatic disease, after the lung and liver. On the other hand, the most frequent bone tumours are metastases and the spine is the main location. A review of the different imaging techniques available, both radiological and nuclear medicine, and the morphological appearance of spinal metastases in each of them is performed. Magnetic resonance imaging is the best imaging modality for detection of spinal metastases. It is important to make the differential diagnosis between vertebral fracture of osteoporotic and pathological cause. Spinal cord compression is a serious complication of metastatic disease and its assessment by imaging through objective scales is decisive for estimating spinal stability and therefore establishing treatment. Lastly, percutaneous intervention techniques are briefly discussed.

Imaging diagnosis of vertebral metastasis. / Diagnóstico por imagen de las metástasis vertebrales.

The spine is the third most frequent location for metastatic disease, after the lung and liver. On the other hand, the most frequent bone tumors are metastases and the spine is the main location. A review of the different imaging techniques available, both radiological and nuclear medicine, and the morphological appearance of spinal metastases in each of them is performed. Magnetic resonance imaging is the best imaging modality for detection of spinal metastases. It is important to make the differential diagnosis between vertebral fracture of osteoporotic and pathological cause. Spinal cord compression is a serious complication of metastatic disease and its assessment by imaging through objective scales is decisive for estimating spinal stability and therefore establishing treatment. Lastly, percutaneous intervention techniques are briefly discussed.

How Does Ball Possession Affect the Physical Demands in Spanish LaLiga? A Multilevel Approach.

Purpose: Using a multilevel approach, this study analyzed the relationship between ball possession and distance covered at different speed sections: total distance (TD), distance covered between 14.1-21 km·h-1 (MIRD), 21.1-24 km·h-1 (HIRD), and > 24.1 km·h-1 (VHIRD). Methods: The sample included 1,520 matches played by 80 Spanish professional soccer teams across four consecutive LaLiga seasons (from 2015/2016 to 2018/2019). Two observations were collected per match, one from each team, resulting in a total of 2,950 records (760 per season). Data were collected using Mediacoach®. Results: At match level (i.e., grand-mean centered), ball possession negatively predicted all distances covered. At team level (i.e., group-mean centered), ball possession negatively predicted total distance covered and distance covered between 14.1-21 km·h-1. Furthermore, cross-level interactions (Match X Team) in ball possession negatively predicted all distances covered at speeds above 14.1 km·h-1. Specifically, in high-possession teams, the negative relationship between match ball possession and distances traveled at all speed ranges above 14.1 km·h-1 was stronger than in teams with medium or low possession. Conversely, match ball possession was positively related todistance covered at low intensities, and negatively related at high intensities in low-possession teams. Conclusion: These findings show practitioners and researchers that the distances covered at different speed ranges depend on technical-tactical parameters such as ball possession.

The relationship between running distance and coaches' perception of team performance in professional soccer player during multiple seasons.

This study analyzed how the physical movement profile of soccer matches evolved throughout a season by assessing the variability of different metrics depending on the season phase. In addition, the evolution of running distances was investigated in the relation to the team performance based on the coaches' perception. Games from four consecutives Spanish LaLiga seasons (n = 1520) were recorded using an optical tracking system (i.e., ChyronHego). Total distance (TD), distance covered between 14 and 21 km h-1 (MIRD), 21-24 km h-1 (HIRD), and > 24 km h-1 (VHIRD) were analyzed, as well as the number of efforts between 21 and 24 km h-1 (Sp21) and > 24 km h-1 (Sp24). Seasons were divided into four phases (P): P1 (matches 1-10), P2 (11-19), P3 (20-29), and P4 (30-38). Linear mixed models revealed that soccer players covered significantly greater distances and completed a higher number of sprints in P2 and P3. Also, team performance evaluated by soccer coaches was positively related to TD, HIRD, VHIRD and Sp21 in P1. A negative relationship was observed between team performance and distance covered at speeds below 21 km h-1 in P2 and P3. Team performance was negatively related to TD, MIRD, and HIRD, and Sp21 in P4. As conclusion, the team performance perceived by coaches is related to the movement profile throughout a season, and it significantly influences the evolution of soccer players' movement profiles. Specifically, it seems that the players of the best teams have the best physical performance at the beginning of the season with respect to the rest of the phases.

Hospitalization due to community-acquired pneumonia in patients with chronic obstructive pulmonary disease: incidence, epidemiology and outcomes.

OBJECTIVES: Community-acquired pneumonia (CAP) is an important complication in patients with chronic obstructive pulmonary disease (COPD). This study aimed to define incidence, and outcomes of COPD patients hospitalized with pneumonia in the city of Louisville, and to estimate the burden of disease in the US population. METHODS: This was a secondary analysis of a prospective population-based cohort study of residents in Louisville, Kentucky, 40 years old and older, from 1 June 2014 to 31 May 2016. All adults hospitalized with CAP were enrolled. The annual incidence of pneumonia in COPD patients in Louisville was calculated and the total number of adults with COPD hospitalized in the United States was estimated. Clinical outcomes included time to clinical stability (TCS), length of hospital stay (LOS) and mortality. RESULTS: From a Louisville population of 18 246 patients with COPD, 3419 pneumonia hospitalizations were documented during the 2-year study. The annual incidence was 9369 patients with pneumonia per 100 000 COPD population, corresponding to an estimated 506 953 adults with COPD hospitalized due to pneumonia in the United States. The incidence of CAP in patients without COPD was 509 (95% CI 485-533) per 100 000. COPD patients had a median (interquartile range) TCS and LOS of 2 (1-4) and 5 (3-9) days respectively. The mortality of COPD patients during hospitalization, at 30 days, 6 months and 1 year was 193 of 3419 (5.6%), 400 of 3374 (11.9%), 816 of 3363 (24.3%) and 1104 of 3349 (33.0%), respectively. CONCLUSIONS: There was an annual incidence of 9369 cases of hospitalized CAP per 100 000 COPD patients in the city of Louisville. This was an approximately 18-fold greater incidence of CAP in COPD patients than in those without COPD.

Bacteremic pneumococcal pneumonia: clinical outcomes and preliminary results of inflammatory response.

PURPOSE: Further examination of clinical outcomes and inflammatory response of bacteremic pneumococcal community-acquired pneumonia (CAP) is of great interest to enhance the care of patients with pneumococcal CAP. METHODS: This is a secondary analysis of the Community Acquired Pneumonia Organization (CAPO) to compare the time to clinical stability (TCS), length of hospital stay (LOS), and in-hospital mortality of hospitalized pneumococcal CAP patients with and without bacteremia. To measure the effect of bacteremia in pneumococcal CAP patients on outcomes, we modeled all-cause in-hospital mortality using a Poisson regression model, and TCS and LOS using Cox proportional hazards models. Adjusted multivariate regression models were also used to predict the probability of occurrence of each of the study outcomes. To investigate the inflammatory response, we measured the plasma levels of pro- and anti-inflammatory cytokines [tumor necrosis factor (TNF)-α, interleukin (IL)-1rα, IL-6, IL-8, IL-10], inflammatory biomarkers [C-reactive protein (CRP), pro-calcitonin (PCT), and B-type natriuretic peptide (BNP)], and peripheral blood neutrophil responses in 10 patients, 4 bacteremic and 6 non-bacteremic pneumococcal CAP, upon admission and every other day during the first 6 days of hospitalization. Functional data were presented as median and standard error of the median (SEM); due to small number of samples no statistical comparisons were performed between groups. RESULTS: From 833 pneumococcal CAP patients, 394 patients (47 %) were bacteremic. Bacteremic pneumococcal CAP were less likely to reach TCS with an adjusted hazard ratio (AHR) of 0.82 (95 % CI 0.69-0.97; p = 0.02) and had higher in-hospital mortality with an AHR of 1.63 (95 % CI 1.06-2.50, p = 0.026). Bacteremic pneumococcal CAP patients had a longer LOS than non-bacteremic pneumococcal CAP (p < 0.003). Higher plasma levels of CRP, PCT, and BNP were found in bacteremic than in non-bacteremic patients. The bacteremic group had consistently higher plasma levels of both pro- and anti-inflammatory cytokines. The blood neutrophil functional responses were similar in both groups of patients. CONCLUSIONS: Bacteremic pneumococcal CAP patients were significantly associated with higher in-hospital mortality, lower TCS, and longer LOS. HIV-infected patients showed a greater mortality which was not statistically significant. Bacteremic pneumococcal CAP patients had higher levels of biomarkers and systemic cytokines.

Nitrofurantoin retains antimicrobial activity against multidrug-resistant urinary Escherichia coli from US outpatients.

OBJECTIVES: To examine the prevalence of multidrug-resistant (MDR) urinary Escherichia coli among US outpatients and to assess the antimicrobial activity of oral antibiotics commonly used to treat urinary tract infections (UTIs) against MDR isolates. METHODS: Antimicrobial susceptibility testing data from outpatient urine cultures in The Surveillance Network (TSN) Database USA were analysed. Six antimicrobial agents from six separate drug classes were included: ampicillin, cefalotin, ciprofloxacin, nitrofurantoin, trimethoprim/sulfamethoxazole and amoxicillin/clavulanate. Isolates were categorized as resistant to one, two, three, four, five and six agents and compared for the years 2001 and 2010. Phenotypes of MDR isolates were assessed to determine antimicrobial activity of recommended therapy for UTIs. RESULTS: Prevalence of MDR E. coli increased from 9.1% in 2001 (n = 29,198) to 17.0% in 2010 (n = 32,742) (P < 0.0001). In isolates that demonstrated resistance to three, four or five antimicrobial agents in 2010, resistance to nitrofurantoin was observed in only 2.1%, 7.5% and 24.1% of isolates, respectively. Conversely, widespread resistance was observed for trimethoprim/sulfamethoxazole (62.6%, 88.6% and 97.9% for isolates resistant to three, four and five agents, respectively) and ciprofloxacin (48.9%, 84.3% and 98.2% for isolates resistant to three, four and five agents, respectively). CONCLUSIONS: Because of its consistent antimicrobial activity against MDR E. coli, nitrofurantoin remains a reliable first-line agent for the empirical treatment of acute uncomplicated cystitis.

Cytokines and neutrophils responses in influenza pneumonia.

This case report shows a striking correlation of remarkable brief high levels of pro- and anti-inflammatory cytokines coupled with increased neutrophil activation, followed by a sharp decrease in cytokine levels and increased neutrophil apoptosis associated with the favorable clinical outcomes of a patient with severe influenza infection. The host response examined in our case is not complete, given it did not assess the full spectrum of host response. The brief neutrophil and cytokine response seen in our case in the absence of antiviral therapy and in the presence of methotrexate immunosuppressive therapy rise the question as to whether the latter optimally modulated the macrophage function, resulting in a favorable outcome of severe influenza viral infection.

Cumulative exposure to stimulants and immune function outcomes among HIV-positive and HIV-negative men in the Multicenter AIDS Cohort Study.

We examined associations between stimulant use (methamphetamine and cocaine) and other substances (nicotine, marijuana, alcohol and inhaled nitrites) with immune function biomarkers among HIV-seropositive (HIV +) men taking highly active antiretroviral therapy (ART) and HIV-seronegative (HIV-) men in the Multicenter AIDS Cohort Study. Among HIV + men, cumulative adherence to ART (4.07, 95% confidence interval [CI]: 3.52, 4.71, per 10 years of adherent ART use), and recent cohort enrolment (1.38; 95% CI: 1.24, 1.55) were multiplicatively associated with increase in CD4+/CD8+ ratios. Cumulative use of methamphetamine (0.93; 95% CI: 0.88, 0.98, per 10 use-years), cocaine (0.93; 95% CI: 0.89, 0.96, per 10 use-years) and cumulative medical visits (0.99; 95% CI: 0.98, 0.99, per 10 visit-years), each showed small negative associations with CD4+/CD8+ ratios. Among HIV- men, cumulative medical visits (0.996; 95% CI: 0.993, 0.999), cumulative number of male sexual partners (0.999; 95% CI: 0.998, 0.9998, per 10 partner-years) and cigarette pack-years (1.10; 95% CI: 1.02, 1.18, per 10 pack-years) were associated with CD4+/CD8+ ratios over the same period. ART adherence is associated with a positive immune function independent of stimulant use, underscoring the influence of ART on immune health for HIV+ men who engage in stimulant use.

Predicting mortality in hospitalized patients with 2009 H1N1 influenza pneumonia.

BACKGROUND: Community-acquired pneumonia (CAP) severity scores can identify patients at low risk for mortality who may be suitable for ambulatory care. Here, we follow the clinical course of hospitalized patients with CAP due to 2009 H1N1 influenza. OBJECTIVE: To evaluate the role of CAP severity scores as predictors of mortality. METHODS: This was a secondary data analysis of patients hospitalized with CAP due to 2009 H1N1 influenza confirmed by reverse transcriptase polymerase chain reaction enrolled in the CAPO (Community-Acquired Pneumonia Organization) international cohort study. CAP severity scores PSI (Pneumonia Severity Index), CURB-65 (confusion, urea, respiratory rate, blood pressure, age ≥ 65 years) and CRB-65 (confusion, respiratory rate, blood pressure, age ≥ 65 years) were calculated. Actual and predicted mortality rates were compared. A total of 37 predictor variables were evaluated to define those associated with mortality. RESULTS: Data from 250 patients with CAP due to 2009 H1N1 influenza were analyzed. Patients with low predicted mortality rates (0-1.5%) had actual mortality rates ranging from 2.6% to 17.5%. Obesity and wheezing were the only novel variables associated with mortality. CONCLUSIONS: The decision to hospitalize a patient with CAP due to 2009 H1N1 influenza should not be based on current CAP severity scores, as they underestimate mortality rates in a significant number of patients. Patients with obesity or wheezing should be considered at an increased risk for mortality.

[Vascular graft-associated infection: successful management without graft removal]. / Infección asociada a prótesis vascular: manejo exitoso sin retirada de prótesis.

INTRODUCTION: Removal of graft with intravenous antibiotics is traditionally considered the most effective treatment of vascular graft-associated infections. However, an increasing number of reports suggests that this complication can be effectively treated without graft removal. METHODS: A prospective study to evaluate the outcome of conservative management of vascular graft-associated infection seen in our center was performed. The diagnosis of graft-associated infection was based on microbiological tests, and imaging studies. In our study, patients were hemodynamically stable with functioning vascular graft as per clinical and imaging evaluations. Conservative management included antibiotic treatment and local debridement without removal of vascular graft. RESULTS: Fourteen patients with vascular graft-associated infection were enrolled in our study. Eleven out of 14 patients (78.6%) responded successfully to conservative management. Treatment failure was reported in 3 patients, 2 of whom required graft removal. After a two-year follow-up, these 14 patients were clinically stable without recurrence of infection. CONCLUSIONS: Our study has revealed that conservative management of vascular graft-associated infection seems to be effective and should be considered in hemodynamically stable patients with functioning vascular graft.

Infección asociada a prótesis vascular: manejo exitoso sin retirada de prótesis / Vascular graft-associated infection: successful management without graft removal

Introducción. La retirada de prótesis con administración de antibióticos endovenosos es tradicionalmente considerada la forma más efectiva para tratar las infecciones asociadas a prótesis vasculares, sin embargo, un incrementado número de trabajos sugieren que esta complicación puede ser efectivamente tratada sin retirar la prótesis. Métodos. Se realiza un estudio prospectivo para evaluar la evolución de manejo conservador de infecciones asociadas a prótesis vasculares vistas en nuestro centro. El diagnóstico de infección asociada a prótesis fue basada en pruebas microbiológicas y en estudios de imagen. En nuestro estudio, los pacientes estuvieron hemodinámicamente estables con buen funcionamiento del injerto demostrado por evaluaciones clínicas y pruebas de imagen. El manejo conservador incluyó tratamiento antibiótico y desbridamiento local sin retirada de la prótesis vascular. Resultados. Incluimos a 14 pacientes con infección asociada a injerto vascular en nuestro estudio. Once de los 14 pacientes (78,6%) respondieron exitosamente al manejo conservador. Observamos fallo en el tratamiento en tres pacientes, dos de los cuales requirieron retirada del injerto. Después de un seguimiento de dos años, todos estos pacientes permanecen estables clínicamente y sin recidiva de la infección. Conclusiones. Como conclusión, nuestro estudio revela que el manejo conservador de prótesis vasculares infectadas parece ser eficaz y debería ser considerado en los pacientes estables hemodinámicamente con buen funcionamiento de la prótesis (AU)

Introduction. Removal of graft with intravenous antibiotics is traditionally considered the most effective treatment of vascular graft-associated infections. However, an increasing number of reports suggests that this complication can be effectively treated without graft removal. Methods. A prospective study to evaluate the outcome of conservative management of vascular graft-associated infection seen in our center was performed. The diagnosis of graft-associated infection was based on microbiological tests, and imaging studies. In our study, patients were hemodynamically stable with functioning vascular graft as per clinical and imaging evaluations. Conservative management included antibiotic treatment and local debridement without removal of vascular graft. Results. Fourteen patients with vascular graft-associated infection were enrolled in our study. Eleven out of 14 patients (78.6%) responded successfully to conservative management. Treatment failure was reported in 3 patients, 2 of whom required graft removal. After a two-year follow-up, these 14 patients were clinically stable without recurrence of infection. Conclusions. Our study has revealed that conservative management of vascular graft-associated infection seems to be effective and should be considered in hemodynamically stable patients with functioning vascular graft (AU)

[Pulmonary hemorrhage and anti-phospholipid syndrome]. / Hemorragia pulmonar y síndrome antifosfolipídico.

The presence of anti-phospholipid antibodies (anticardiolipin antibodies and lupus anticoagulant) associated to venous and/or arterial thrombotic phenomena and fetal losses define the anti-phospholipid syndrome. On rare occasions severe hypoprothrombinemia associated with this disease as a cause of hemorrhagic manifestations has been described. In addition very few cases of alveolar hemorrhage in anti-phospolipid syndrome (APS) have been described, being this complication usually related to microthrombosis and/or capillaritis of pulmonary vessels. We describe two patients without previous clinical manifestations of anti-phospholipid syndrome that showed pulmonary hemorrhage with anticardiolipin antibodies positivity. The first of them, a 33-year-old male, began his disease with low prothrombin time and the presence of antiprothrombin antibodies. In the biopsy by thoracoscopy the presence of pulmonary hemorrhage without capillaritis nor thrombotic phenomena was demonstrated, becoming evident certain clinical improvement and normalization of the prothrombin time after receiving immunosuppressive treatment but with persistence of the pulmonary hemorrhage 5 years later. The second case, a 89-year-old male, began his condition with bilateral lung infiltrates and hemoptysis, anticardiolipin antibodies positivity, and thrombopenia, with recurrence of the condition 1 year later. After other etiological possibilities were ruled out, and despite hemorrhagic trait in both patients, we consider that they should be in the clinical context of the anti-phospholipid syndrome, although at this time they did not meet the criteria recognized in order to diagnose this disease. Within the ampliable clinical spectrum of the anti-phospholipid syndrome we should take into account the pulmonary hemorrhage.

Early switch from intravenous to oral antibiotics in hospitalized patients with bacteremic community-acquired Streptococcus pneumoniae pneumonia.

BACKGROUND: The identification of Streptococcus pneumoniae bacteremia in hospitalized patients with community-acquired pneumonia is considered by some investigators to be an exclusion criterion for early switch from intravenous to oral therapy. OBJECTIVE: To determine whether the switch from intravenous to oral therapy in such patients, once the bx;1patient reaches clinical stability, is associated with poor clinical outcome. METHODS: The medical records of 400 patients with community-acquired pneumonia hospitalized at the Veterans Affairs Medical Center of Louisville (Louisville, Ky) were reviewed to identify patients with bacteremic S pneumoniae. Four criteria were used to define when a patient reached clinical stability and should be considered a candidate for switch therapy: (1) cough and shortness of breath are improving, (2) patient is afebrile for at least 8 hours, (3) white blood cell count is normalizing, and (4) oral intake and gastrointestinal tract absorption are adequate. RESULTS: A total of 36 bacteremic patients were identified. No clinical failures occurred in 18 patients who reached clinical stability and were switched to oral therapy or in 7 patients who reached clinical stability and continued intravenous therapy. Clinical failures (5 deaths) occurred in the group of 11 patients who did not reach clinical stability. CONCLUSION: Once a hospitalized patient with community-acquired pneumonia reaches clinical stability, it is safe to switch from intravenous to oral antibiotics even if bacteremia caused by S pneumoniae was initially documented.

Response to standard syphilis treatment in patients infected with the human immunodeficiency virus.

In a study designed to evaluate the efficacy of penicillin in HIV-infected patients with syphilis and to determine the clinical and laboratory responses after treatment, 13 patients with HIV infection and syphilis were assessed at enrollment and at the last follow-up examination (median time of 21 months). The Venereal Diseases Research Laboratory (VDRL) test, the Treponema pallidum hemaglutination test, and leukocyte counts in cerebrospinal fluid were evaluated both at enrollment and at the last follow-up visit, and the polymerase chain reaction for Treponema pallidum DNA and the rabbit infectivity test were performed on cerebrospinal fluid samples at the last follow-up visit. Primary syphilis was confirmed in four patients, latent syphilis in five, and neurosyphilis in four. After penicillin treatment, all patients were asymptomatic. The serum rapid plasma reagin test became negative in five patients, and titers declined in eight. The VDRL test, Treponema pallidum DNA, and the rabbit infectivity test were negative in all 13 patients. Except for one patient whose serological titer was slow to decline, all patients had good clinical and serological responses to penicillin. In certain settings, factors other than penicillin treatment failure should be considered in HIV-infected patients with suspected relapse of syphilis.