Unusual cutaneous metastatic carcinoma.

Most of metastatic tumors to the skin are from primary tumors of the breast, lung, or from melanoma; metastases to the skin from primary carcinomas at other sites are rare. Cutaneous metastases of visceral carcinomas most often occur in patients with advanced disease, and are associated with a poor prognosis. We report 6 cases of nonmammary, nonpulmonary carcinoma metastatic to the skin. Most patients were elderly with advanced disease at the time of diagnosis of skin metastasis. The primary tumor sites included the thyroid, esophagus, biliary tract, ovary, and prostate. Awareness of these rare cases of metastasis to the skin will help pathologists and clinicians make the correct diagnosis.

CD4/CD8 Ratio in Mediastinal Lymph Nodes Involved by Sarcoidosis: Analysis of Flow Cytometry Data Obtained by Endobronchial Ultrasound-guided Transbronchial Needle Aspiration.

BACKGROUND: Despite mixed results in the literature, some clinicians continue to consider an elevated CD4/CD8 ratio in bronchoalveolar lavage (BAL) fluid to be supportive of a diagnosis of sarcoidosis. However, the CD4/CD8 ratio in mediastinal lymph nodes involved by sarcoidosis has not been extensively studied. The primary aim of this study was to evaluate the utility of the CD4/CD8 ratio in mediastinal lymph node aspirates obtained by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for diagnosing sarcoidosis. METHODS: Our archives were searched for EBUS-TBNAs in which mediastinal lymph node aspirates had been submitted for flow cytometry (n=160). Clinical and pathologic findings in these cases were reviewed retrospectively. Cases were included in the study if they had (1) a clinical diagnosis of sarcoidosis supported by cytopathologic confirmation of non-necrotizing granulomas in EBUS-TBNA-derived lymph node aspirates (23 cases), or (2) a pathologically confirmed non-neoplastic diagnosis other than sarcoidosis (7 cases). Cases that did not fulfil these criteria were excluded (130 cases). RESULTS: The CD4/CD8 ratios in mediastinal lymph nodes and BAL fluid were compared. The CD4/CD8 ratio was elevated in mediastinal lymph nodes in 12/23 (52%) cases of sarcoidosis and 3/7 (43%) pathologically confirmed nonsarcoid cases. BAL fluid had been concurrently submitted for flow cytometry in 20/23 cases of sarcoidosis and 5/7 nonsarcoid cases. CD4/CD8 was elevated in BAL fluid in 9/20 (45%) cases of sarcoidosis and 2/5 (40%) nonsarcoid cases. CONCLUSION: As in BAL fluid, the CD4/CD8 ratio in mediastinal lymph nodes involved by sarcoid granulomas is highly variable and does not reliably confirm or exclude sarcoidosis.

Hyperpigmented cutaneous lesions that flare-up with scratching: Darier's sign.

We present the case of a 40-year-old male with a past medical history of urticaria pigmentosa (UP) who presented for consultation to the Allergy clinic for an opinion of systemic mastocytosis. Previous workups included elevated serum tryptase level, UP on skin biopsy and an increased number of CD117-positive/CD25-positive mast cells on bone marrow biopsy. This case emphasizes the importance of physical findings such as Darier's sign in patients with hyperpigmented lesions, which virtually supports the diagnosis UP, raises the suspicion for systemic mastocytosis and guides further diagnostic evaluation. This case also outlines the management of systemic mastocytosis.

Current status of carbapenemases in Latin America.

Enterobacteriaceae and non fermenting Gram-negative bacilli have become a threat to public health, in part due to their resistance to multiple antibiotic classes, which ultimately have led to an increase in morbidity and mortality. ß-lactams are currently the mainstay for combating infections caused by these microorganisms, and ß-lactamases are the major mechanism of resistance to this class of antibiotics. Within the ß-lactamases, carbapenemases pose one of the gravest threats, as they compromise one of our most potent lines of defense, the carbapenems. Carbapenemases are being continuously identified worldwide; and in Latin America, numerous members of these enzymes have been reported. In this region, the high incidence of reports implies that carbapenemases have become a menace and that they are an issue that must be carefully studied and analyzed.

First identification of OXA-72 carbapenemase from Acinetobacter pittii in Colombia.

OXA-72 has been reported in few countries around the world. We report the first case in Colombia in an Acinetobacter pittii clinical isolate. The arrival of a new OXA, into a country with high endemic resistance, poses a significant threat, especially because the potential for widespread dissemination is considerable.

Assessing the pharmacodynamic profile of intravenous antibiotics against prevalent Gram-negative organisms collected in Colombia

OBJECTIVES: This study was designed to simulate standard and optimized dosing regimens for intravenous antibiotics against contemporary populations of Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa using MIC distribution data to determine which of the tested carbapenem regimens provided the greatest opportunity for obtaining maximal pharmacodynamic (PD) activity. METHODS: The isolates studied were obtained from the COMPACT-COLOMBIA surveillance program conducted between February and November 2009. Antimicrobial susceptibility testing was conducted by broth microdilution method according to the CLSI guidelines. Doripenem, imipenem-cilastatin, and meropenem, were the modeled antibiotics. A 5,000 patient Monte Carlo simulation was performed for each regimen and PD targets were defined as free drug concentrations above the MIC for at least 40 percent of the dosing interval. RESULTS: All carbapenem regimens obtained optimal exposures against E. coli, unlike the other Enterobacteriaceae tested. Against P. aeruginosa, only a prolonged infusion of doripenem exceeded the 90 percent cumulative fraction of response (CFR) threshold. Worrisomely, no regimens for any of the drugs tested obtained optimal CFR against A. baumannii. For P. aeruginosa intensive care unit (ICU) isolates, CFR was approximately 20 percent lower for isolates collected in the respiratory tract compared with bloodstream or intra-abdominal for imipenem and meropenem. Noteworthy, all doripenem and meropenem regimens achieved greater than 90 percent CFR against bloodstream and respiratory isolates of K. pneumoniae. CONCLUSIONS: Our data suggests that higher dosing and prolonged infusion of doripenem or meropenem may be suitable for empirically treating ICU P. aeruginosa, while none of the carbapenems achieved optimal cumulative fraction of response against A. baumannii. Standard dosing regimens of all the carbapenems tested achieved optimal CFR against E. coli isolates, but higher carbapenem dosages might be required for empiric treatment of K. pneumoniae, particularly from an intra-abdominal source. Non-standard dosage regimens studied in this modeling should be proven effective in prospective clinical trials.

Papel de la clorhexidina en la prevención de las infecciones asociadas a la atención en salud / Role of chlorhexidine in the prevention of health care related infections

Las infecciones asociadas a la atención en salud son uno de los eventos secundarios más comunes entre los pacientes hospitalizados. Estas infecciones se relacionan con incrementos en la morbilidad, la mortalidad, la estancia hospitalaria y los costos asociados a la atención en salud. La clorhexidina ha probado ser útil en la prevención de infecciones asociadas a la atención en salud, debido a su amplio espectro antiséptico, su eficacia y su margen de seguridad. Diferentes estudios han demostrado efectividad de la clorhexidina en la prevención de infecciones tales como las del sitio operatorio, la bacteriemia asociada al catéter vascular, la neumonía asociada al respirador, las infecciones maternas y neonatales, y otras infecciones causadas por Staphylococcus aureus. La mayoría de los estudios han encontrando superioridad de este compuesto sobre otros antisépticos, en la prevención y control de infecciones asociadas a la salud.

Health care related infections are one of the most common adverse events among hospitalized patients. These types of infections are related to an increased morbidity, mortality, hospitalization time, and health care related costs. Chlorhexidine has been proven to be useful for preventing health care related infections due to its wide antiseptic spectrum, effectiveness and safety. Different studies have shown evidence about the effectiveness of chlorhexidine in the prevention of infections related to surgical sites, vascular catheter related bloodstream infections, ventilator associated pneumonia, maternal and neonatal infections and other infections caused by Staphylococcus aureus. Most studies have found superiority of this compound against other antiseptics in the prevention and control of health care related infections.

Novel VIM metallo-beta-lactamase variant, VIM-24, from a Klebsiella pneumoniae isolate from Colombia.

We report the emergence of a novel VIM variant (VIM-24) in a Klebsiella pneumoniae isolate in Colombia. The isolate displays MICs for carbapenems below the resistance breakpoints, posing a real challenge for its detection. The blaVIM-24 gene was located within a class 1 integron carried on a large plasmid. Further studies are needed to clarify its epidemiological and clinical impact.

First characterization of CTX-M-15-producing Escherichia coli ST131 and ST405 clones causing community-onset infections in South America.

CTX-M-15-producing Escherichia coli has emerged worldwide as an important pathogen associated with community-onset infections, but in South America reports are scarce. We document the presence of CTX-M-15-producing E. coli of the international ST131 and ST405 clones in Colombia and present the first molecular characterization of these isolates in South America.

Assessing the pharmacodynamic profile of intravenous antibiotics against prevalent Gram-negative organisms collected in Colombia.

OBJECTIVES: This study was designed to simulate standard and optimized dosing regimens for intravenous antibiotics against contemporary populations of Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa using MIC distribution data to determine which of the tested carbapenem regimens provided the greatest opportunity for obtaining maximal pharmacodynamic (PD) activity. METHODS: The isolates studied were obtained from the COMPACT-COLOMBIA surveillance program conducted between February and November 2009. Antimicrobial susceptibility testing was conducted by broth microdilution method according to the CLSI guidelines. Doripenem, imipenem-cilastatin, and meropenem, were the modeled antibiotics. A 5,000 patient Monte Carlo simulation was performed for each regimen and PD targets were defined as free drug concentrations above the MIC for at least 40% of the dosing interval. RESULTS: All carbapenem regimens obtained optimal exposures against E. coli, unlike the other Enterobacteriaceae tested. Against P. aeruginosa, only a prolonged infusion of doripenem exceeded the 90% cumulative fraction of response (CFR) threshold. Worrisomely, no regimens for any of the drugs tested obtained optimal CFR against A. baumannii. For P. aeruginosa intensive care unit (ICU) isolates, CFR was approximately 20% lower for isolates collected in the respiratory tract compared with bloodstream or intra-abdominal for imipenem and meropenem. Noteworthy, all doripenem and meropenem regimens achieved greater than 90% CFR against bloodstream and respiratory isolates of K. pneumoniae. CONCLUSIONS: Our data suggests that higher dosing and prolonged infusion of doripenem or meropenem may be suitable for empirically treating ICU P. aeruginosa, while none of the carbapenems achieved optimal cumulative fraction of response against A. baumannii. Standard dosing regimens of all the carbapenems tested achieved optimal CFR against E. coli isolates, but higher carbapenem dosages might be required for empiric treatment of K. pneumoniae, particularly from an intra-abdominal source. Non-standard dosage regimens studied in this modeling should be proven effective in prospective clinical trials.