Neratinib + fulvestrant + trastuzumab for HR-positive, HER2-negative, HER2-mutant metastatic breast cancer: outcomes and biomarker analysis from the SUMMIT trial.

BACKGROUND: HER2 mutations are targetable alterations in patients with hormone receptor-positive (HR+) metastatic breast cancer (MBC). In the SUMMIT basket study, patients with HER2-mutant MBC received neratinib monotherapy, neratinib + fulvestrant, or neratinib + fulvestrant + trastuzumab (N + F + T). We report results from 71 patients with HR+, HER2-mutant MBC, including 21 (seven in each arm) from a randomized substudy of fulvestrant versus fulvestrant + trastuzumab (F + T) versus N + F + T. PATIENTS AND METHODS: Patients with HR+ HER2-negative MBC with activating HER2 mutation(s) and prior cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) therapy received N + F + T (oral neratinib 240 mg/day with loperamide prophylaxis, intramuscular fulvestrant 500 mg on days 1, 15, and 29 of cycle 1 then q4w, intravenous trastuzumab 8 mg/kg then 6 mg/kg q3w) or F + T or fulvestrant alone. Those whose disease progressed on F + T or fulvestrant could cross-over to N + F + T. Efficacy endpoints included investigator-assessed objective response rate (ORR), clinical benefit rate (RECIST v1.1), duration of response, and progression-free survival (PFS). Plasma and/or formalin-fixed paraffin-embedded tissue samples were collected at baseline; plasma was collected during and at end of treatment. Extracted DNA was analyzed by next-generation sequencing. RESULTS: ORR for 57 N + F + T-treated patients was 39% [95% confidence interval (CI) 26% to 52%); median PFS was 8.3 months (95% CI 6.0-15.1 months). No responses occurred in fulvestrant- or F + T-treated patients; responses in patients crossing over to N + F + T supported the requirement for neratinib in the triplet. Responses were observed in patients with ductal and lobular histology, 1 or ≥1 HER2 mutations, and co-occurring HER3 mutations. Longitudinal circulating tumor DNA sequencing revealed acquisition of additional HER2 alterations, and mutations in genes including PIK3CA, enabling further precision targeting and possible re-response. CONCLUSIONS: The benefit of N + F + T for HR+ HER2-mutant MBC after progression on CDK4/6is is clinically meaningful and, based on this study, N + F + T has been included in the National Comprehensive Cancer Network treatment guidelines. SUMMIT has improved our understanding of the translational implications of targeting HER2 mutations with neratinib-based therapy.

Diagnostic performance of serological tests for swine brucellosis in the presence of false positive serological reactions.

Swine brucellosis caused by Brucella suis biovar 2 is an emerging disease in Europe. Currently used diagnostic tests for swine brucellosis detect antibodies to the O-polysaccharide (O-PS) of Brucella smooth lipopolysaccharide (S-LPS) but their specificity is compromised by false-positive serological reactions (FPSRs) when bacteria carrying cross-reacting O-PS infect pigs. FPSRs occur throughout Europe, and the only tool available for a specific B. suis diagnosis is the intradermal test with Brucella protein extracts free of O-PS or S-LPS. Using sera of 162 sows naturally infected by B. suis biovar 2, 406 brucellosis-free sows, and 218 pigs of brucellosis-free farms affected by FPSR, we assessed the diagnostic performance of an indirect ELISA with rough LPS (thus devoid of O-PS) and of gel immunodiffusion, counterimmunoelectrophoresis, latex agglutination and indirect ELISA with O-PS free proteins in comparison with several S-LPS tests (Rose Bengal, complement fixation, gel immunodiffusion and indirect ELISA). When adjusted to 100% specificity, the sensitivity of the rough LPS ELISA was very low (30%), and adoption of other cut-offs resulted in poor specificity/sensitivity ratios. Although their specificity was 100%, the sensitivity of protein tests (ELISA, latex agglutination, counterimmunoelectrophoresis, and gel immunodiffusion) was only moderate (45, 58, 61 and 63%, respectively). Among S-LPS tests, gel immunodiffusion was the only test showing acceptable sensitivity/specificity (68 and 100%, respectively). Despite these shortcomings, and when the purpose is to screen out FPSR at herd level, gel immunodiffusion tests may offer a technically simple and practical alternative to intradermal testing.

Studies on a suitable antibiotic therapy for treating swine brucellosis.

The aim of this work was developing effective treatments against Brucella suis biovar 2, responsible for swine brucellosis in Europe. MICs for antibiotics used classically in brucellosis and two new macrolides (tulathromycin and tildipirosin) were determined for 33 B. suis biovar 2 field and B. suis reference strains. MIC90 values ranged from 0.01 to 0.25 µg/mL. The best candidates, given alone or combined, were then evaluated in mice. Ten groups (n = 7) of BALB/c mice were inoculated (1 × 10(5) CFU/mouse) with a virulent B. suis biovar 2 field strain. All groups, excepting untreated control, were treated for 14 days with, respectively, doxycycline, dihydrostreptomycin, tulathromycin (one or two doses), or tildipirosin (one or two doses) given alone, and doxycycline combined with dihydrostreptomycin, tulathromycin, or tildipirosin. Combined tildipirosin treatment was the most effective, then selected for pig studies. Sixteen B. suis biovar 2 naturally infected sows were treated with oxytetracycline (20 mg/kg BW/daily) for 21 days. The half of these received also tildipirosin (4 mg/kg BW) in two doses with a 10-day interval. An extensive bacteriological study conducted ten days after ceasing treatments proved the efficacy of this combined oxytetracycline/tildipirosin treatment.

Performance of skin tests with allergens from B. melitensis B115 and rough B. abortus mutants for diagnosing swine brucellosis.

Swine brucellosis by Brucella suis biovar 2 is an emerging disease whose control is based on serological testing and culling. However, current serological tests detect antibodies to the O-polysaccharide (O/PS) moiety of Brucella smooth lipopolysaccharide (S-LPS), and thus lack specificity when infections by Yersinia enterocolitica O:9 and other gram-negative bacteria carrying cross-reacting O/PS occur. The skin test with the protein-rich brucellin extract obtained from rough B. melitensis B115 is assumed to be specific for discriminating these false positive serological reactions (FPSR). However, B115 strain, although unable to synthesize S-LPS, accumulates O/PS internally, which could cause diagnostic problems. Since the brucellin skin test has been seldom used in pigs and FPSR are common in these animals, we assessed its performance using cytosoluble protein extracts obtained from B. abortus rough mutants in manBcore or per genes (critical for O/PS biosynthesis) and B. melitensis B115. The diagnostic sensitivity and specificity were determined in B. suis biovar 2 culture positive and brucellosis free sows, and apparent prevalence in sows of unknown individual bacteriological and serological status belonging to B. suis biovar 2 naturally infected herds. Moreover, the specificity in discriminating brucellosis from FPSR was assessed in brucellosis free boars showing FPSR. The skin test with B. abortus ΔmanBcore and B. melitensis B115 allergens performed similarly, and the former one resulted in 100% specificity when testing animals showing FPSR in indirect ELISA, Rose Bengal and complement fixation serological tests. We conclude that O/PS-free genetically defined mutants represent an appropriate alternative to obtain Brucella protein extracts for diagnosing swine brucellosis.

Development of a selective culture medium for primary isolation of the main Brucella species.

Bacteriological diagnosis of brucellosis is performed by culturing animal samples directly on both Farrell medium (FM) and modified Thayer-Martin medium (mTM). However, despite inhibiting most contaminating microorganisms, FM also inhibits the growth of Brucella ovis and some B. melitensis and B. abortus strains. In contrast, mTM is adequate for growth of all Brucella species but only partially inhibitory for contaminants. Moreover, the performance of both culture media for isolating B. suis has never been established properly. We first determined the performance of both media for B. suis isolation, proving that FM significantly inhibits B. suis growth. We also determined the susceptibility of B. suis to the antibiotics contained in both selective media, proving that nalidixic acid and bacitracin are highly inhibitory, thus explaining the reduced performance of FM for B. suis isolation. Based on these results, a new selective medium (CITA) containing vancomycin, colistin, nystatin, nitrofurantoin, and amphotericin B was tested for isolation of the main Brucella species, including B. suis. CITA's performance was evaluated using reference contaminant strains but also field samples taken from brucella-infected animals or animals suspected of infection. CITA inhibited most contaminant microorganisms but allowed the growth of all Brucella species, to levels similar to those for both the control medium without antibiotics and mTM. Moreover, CITA medium was more sensitive than both mTM and FM for isolating all Brucella species from field samples. Altogether, these results demonstrate the adequate performance of CITA medium for the primary isolation of the main Brucella species, including B. suis.

Efficacy of bp26 and bp26/omp31 B. melitensis Rev.1 deletion mutants against Brucella ovis in rams.

Brucella melitensis Rev.1 is the most effective vaccine against B. ovis infection in sheep but induces antibodies interfering with B. melitensis diagnosis. Brucella BP26 and Omp31 proteins are differential diagnostic antigens. Single or double bp26 and omp31 Rev.1 deletion mutants have been proven effective against B. melitensis in sheep. Here, the CGV26 (deleted in bp26 gene) and CGV2631 (deleted in both bp26 and omp31 genes) mutants have been tested for efficacy against B. ovis in rams. Either inoculated subcutaneously or conjunctivally, both mutants conferred significant protection against B. ovis. The protection induced by CGV26 was similar to that of Rev.1 but significantly higher than that conferred by CGV2631. In conclusion, the CGV26 mutant, in association with the adequate diagnostic strategy, could be a useful alternative to Rev.1 for sheep vaccination against B. ovis infections in those countries performing simultaneously B. melitensis and B. ovis eradication campaigns.

Evaluation of a multiplex PCR assay (Bruce-ladder) for molecular typing of all Brucella species, including the vaccine strains.

An evaluation of a multiplex PCR assay (Bruce-ladder) was performed in seven laboratories using 625 Brucella strains from different animal and geographical origins. This robust test can differentiate in a single step all of the classical Brucella species, including those found in marine mammals and the S19, RB51, and Rev.1 vaccine strains.

Efficacy of several antibiotic combinations against Brucella melitensis Rev 1 experimental infection in BALB/c mice.

OBJECTIVES: The objective of the present study was to compare the efficacy of gentamicin given alone or combined with doxycycline with that of standard combination therapies in BALB/c mice experimentally infected with the Brucella melitensis vaccine strain Rev 1. METHODS: A standard broth microdilution method was applied to determine the susceptibility of strain Rev 1 to the clinically most relevant aminoglycosides. Eight groups of BALB/c mice were inoculated intraperitoneally (ip) with 1 x 10(6) cfu/mouse of strain Rev 1. While one group remained untreated, the other seven groups were treated 10 days later once a day for 14 days with (i) doxycycline given orally at 2 mg/day; (ii) streptomycin given ip at 0.4 mg/day; (iii) gentamicin given ip at 0.4 mg/day; (iv) rifampicin given orally at 0.5 mg/day; (v) doxycycline plus streptomycin; (vi) doxycycline plus gentamicin; and (vii) doxycycline plus rifampicin. The number of cfu per spleen and clearance of Rev 1 were assessed 34 days after inoculation. RESULTS: With the exception of streptomycin, strain Rev 1 was susceptible to all aminoglycosides tested. As expected, the combination doxycycline/streptomycin was ineffective against Rev 1 infection. In contrast, the combinations doxycycline/gentamicin and doxycycline/rifampicin were effective in the clearance of Rev 1 infection, but only the former improved significantly the therapeutic efficacy as compared with that of the antibiotics given alone. CONCLUSIONS: Gentamicin may be used along with doxycycline when the classical combination is considered the first choice in the treatment of patients with brucellosis due to B. melitensis vaccine strain Rev 1.

[Short course treatment for visceral leishmaniasis with liposomal amphotericin B in immunocompetent patients]. / Tratamiento de corta duración de la leishmaniasis visceral con anfotericina B liposómica en pacientes inmunocompetentes.

INTRODUCTION: Visceral leishmaniasis is endemic in southern Europe. Traditional treatment consists of pentavalent antimonial compounds. However, treatment failures, the treatment's long duration, and toxicity have led to the introduction of new therapies, such as liposomal amphotericin B (LAB). In this study we evaluate the safety and efficacy of LAB at a maximum dose of 4 mg/kg/day on days 1, 2, 3, 4, 5, and 10. PATIENTS AND METHODS: A prospective, observational, open study was conducted in 13 Spanish centers. The diagnosis of visceral leishmaniasis was based on visualization of Leishmanias sp. in bone marrow aspirate or culture or positive serology together with compatible clinical symptoms. RESULTS: Thirty-two immunocompetent children aged from 7 months to 7 years were treated. All the children had rapid clinical response and bone marrow aspirate performed on day 21 was normal in the 24 patients (100 %) who underwent this procedure. In the remaining eight children efficacy was assessed by clinical response. Two relapses were observed. Cure was achieved in 18 patients (90.0 %) and in 87.5 % of the patients with microbiological confirmation of the disease. No adverse events were detected. CONCLUSIONS: A total dosage of 24 mg/kg of liposomal amphotericin B administered in 6 doses within 10 days is safe and effective for the treatment of visceral leishmaniasis and reduces the length of hospital stay.

Achromobacter xylosoxidans bacteremia: a 10-year analysis of 54 cases.

Fifty-four cases of Achromobacter xylosoxidans bacteremia diagnosed over a 10-year period in patients from 2 months to 87 years of age were reviewed. Fifty-two episodes were nosocomial. The most frequent underlying condition was neoplasm (solid or hematological). The source of infection was a contaminated intravenous catheter in 35 patients (60%) and pneumonia in 6 patients. Eight (15%) patients died. The only risk factors significantly associated with mortality were age over 65 years and neutropenia. The results of in vitro susceptibility studies of the isolates showed that antibiotic therapy with antipseudomonal penicillins or carbapenems would be a reasonable choice. An epidemiological study conducted in the hemodialysis unit showed Achromobacter xylosoxidans in tap water and on the hands of two healthcare workers but not in the hemodialysis systems. Patients were probably contaminated when healthcare workers manipulated the intravenous catheters without wearing gloves.

Characterization of Brucella abortus O-polysaccharide and core lipopolysaccharide mutants and demonstration that a complete core is required for rough vaccines to be efficient against Brucella abortus and Brucella ovis in the mouse model.

Brucella abortus rough lipopolysaccharide (LPS) mutants were obtained by transposon insertion into two wbk genes (wbkA [putative glycosyltransferase; formerly rfbU] and per [perosamine synthetase]), into manB (pmm [phosphomannomutase; formerly rfbK]), and into an unassigned gene. Consistent with gene-predicted roles, electrophoretic analysis, 2-keto-3-manno-D-octulosonate measurements, and immunoblots with monoclonal antibodies to O-polysaccharide, outer and inner core epitopes showed no O-polysaccharide expression and no LPS core defects in the wbk mutants. The rough LPS of manB mutant lacked the outer core epitope and the gene was designated manB(core) to distinguish it from the wbk manB(O-Ag). The fourth gene (provisionally designated wa**) coded for a putative glycosyltransferase involved in inner core synthesis, but the mutant kept the outer core epitope. Differences in phage and polymyxin sensitivity, exposure or expression of outer membrane protein, core and lipid A epitopes, and lipid A acylation demonstrated that small changes in LPS core caused significant differences in B. abortus outer membrane topology. In mice, the mutants showed different degrees of attenuation and induced antibodies to rough LPS and outer membrane proteins. Core-defective mutants and strain RB51 were ineffective vaccines against B. abortus in mice. The mutants per and wbkA induced protection but less than the standard smooth vaccine S19, and controls suggested that anti O-polysaccharide antibodies accounted largely for the difference. Whereas no core-defective mutant was effective against B. ovis, S19, RB51, and the wbkA and per mutants afforded similar levels of protection. These results suggest that rough Brucella vaccines should carry a complete core for maximal effectiveness.

[Brain stem encephalitis in childhood]. / Encefalitis de tronco cerebral en la infancia.

OBJECTIVE: To present two cases of post-infectious encephalitis of the brain stem (ETC) in infancy, which is very infrequent at this age. CLINICAL CASES: Two patients aged 4 months and 9 months respectively had a previous history of a catarrhal illness a few days before the onset of encephalitis. The clinical condition was of subacute onset and torpid course, characterized by ataxia, reduced level of consciousness, involvement of the pyramidal tracts and paralysis of the cranial nerves. No significant information for the diagnosis of either case was obtained from CT. MR showed lesions at the level of the pons. However, the MR image did not correspond in seventy to the clinical condition. The clinical courses of the two patients were different. One case recovered with no sequelae. In the other case the cranial nerves and gait did not return to normal. CONCLUSIONS: In our experience, ETC is rarely seen in infancy. A high degree of suspicion and early treatment of ETC caused by the herpes simplex virus is necessary, since there is usually a high mortality or serious neurological sequelae.

Sepsis in children with human immunodeficiency virus infection. The Madrid HIV Pediatric Infection Collaborative Study Group.

The aims of this retrospective study were to review the frequency and patterns of bacterial sepsis in children infected with human immunodeficiency virus. The charts of 233 human immunodeficiency virus-infected children cared for during a 10-year period in 4 tertiary hospitals in Madrid were reviewed. There were 43 episodes of sepsis in 31 (13%) children. Twenty of them had acquired immunodeficiency syndrome, 10 were class PA2 and 1 was class P1B. The most common organisms recovered were: nontyphoidal Salmonella, 10 cases (23%); Streptococcus pneumoniae, 9 cases (21%); Staphylococcus epidermidis, 6 cases (14%); Escherichia coli, 5 cases (12%); Enterococcus faecalis, 4 cases (9%); Campylobacter jejuni, 2 cases (5%). In 28 episodes of bacteremia there were other sites of associated infection: pneumonia, 6 cases; urinary tract infection (UTI), 5 cases; gastrointestinal disease, 4 cases; catheter-related bacteremia, 12 cases. Eight patients had more than 1 episode of bacteremia. The rate of complications was high: 6 children had septic shock; and 2 of them developed disseminated intravascular coagulation. There was 1 death directly related to sepsis.

[Chemoprophylaxis of tuberculosis: compliance to treatment in the pediatric population]. / Quimioprofilaxis tuberculosa: grado de cumplimiento en la población pediátrica.

We have reviewed the success of tuberculosis chemoprophylaxis in 369 children. These children ranged from 4 months to 14 years of age and had been prescribed chemoprophylaxis with Isoniazide at 10 mg/kg/day. Out of these, 258 (69.91%) finished the prophylaxis and 111 (30.08%) did not. Taking into account the reason for the consultation, of those who sought assistance due to contact with a patient with tuberculosis, 70.33% performed the treatment and 29.60% did not. For those in which the reason was a positive Mantoux, the data were 68.1% and 30.8%, respectively. No statistically significant differences were found between the two groups. We feel that the relatively high rate of noncompliance in our patients is a matter of concern. At the present time, chemoprophylaxis with Isoniazide is the best method available for the prevention of tuberculosis. We emphasize the need for its proper performance. We report several measures, such as the determination of Isoniazide metabolites in urine, which may be beneficial for better control and follow-up of these patients.

[Pulmonary tuberculosis in infants: apropos of 149 cases]. / Tuberculosis pulmonar en la infancia: a propósito de 149 casos.

One hundred and forty-nine cases of childhood pulmonary tuberculosis were analysed being a 77.6% of the 192 cases of tuberculosis diagnosed at the Pediatric Infectious Diseases Department of "La Paz" Hospital, in a ten year period. The children were aged 3 months to 14 years; 65% of them were less than 6 years of age. The source case was found in 67.1% of the children. The primary means of diagnosis was contact screening (38.1%), followed by a 27.5% that presented with non-specific symptoms, while 18.1% of the cases presented with respiratory symptoms. Gastric aspirates yield the organism in 25.8% of cases. Radiologically the following was found: 38.9% mixed patterns, 32.2% nodal patterns, 23.4% parenchymal patterns, 1.34 miliary tuberculosis, 1.34% caverns and 2.68% pleural effusions. Right lung location was more frequent in parenchymatous forms (68%), as well as in nodal forms (61.5%). The duration of the course of therapy changed along this ten years period: from twelve months initially to ten months posteriorly, subsequently becoming a six month course of treatment. All cases experienced full recovery.