Conversion to mTOR Inhibitor to Reduce the Incidence of Cytomegalovirus Recurrence in Kidney Transplant Recipients Receiving Preemptive Treatment: A Prospective, Randomized Trial

BACKGROUND

Although mammalian target of rapamycin inhibitors (mTORi) are associated with a lower incidence of the first episode of cytomegalovirus (CMV) infection/disease in kidney transplant recipients receiving calcineurin inhibitors (CNIs), the efficacy and safety of the conversion from the antimetabolite to an mTORi for the prevention of CMV recurrence are unknown.

METHODS

In this single-center prospective randomized trial, low-immunological-risk, CMV-positive kidney transplant recipients receiving preemptive therapy were randomized to be converted (sirolimus [SRL]) or not (control [CTR]) immediately after the treatment of the first episode of CMV infection/disease and were followed for 12 mo. A sample size of 72 patients was calculated to demonstrate a 75% reduction in the incidence of CMV recurrence (80% power, 95% confidence level).

RESULTS

Of 3247 adult kidney transplants performed between September 13, 2015, and May 7, 2019, 1309 (40%) were treated for the first CMV infection/disease, and 72 were randomized (35 SRL and 37 CTR). In the SRL group, there were no episodes of CMV recurrence, compared with 16 patients in the CTR group (0% versus 43%; P  < 0.0001). Four patients had a second and 1 a third recurrent CMV event. Three of them were converted to SRL and did not develop any further CMV events. There were no differences in the incidence of acute rejection, drug discontinuation, kidney function, and patient and graft survival at 12 mo.

CONCLUSIONS

These data suggest that, in CMV-positive kidney transplant recipients, the conversion from an antiproliferative drug to SRL after the first CMV episode is an effective and safe strategy for recurrent episodes.

In vitro activity of isavuconazole against clinically relevant Trichosporon species: a comparative evaluation of EUCAST broth microdilution and MIC Test Strip methods

OBJECTIVES

To evaluate the in vitro activity of isavuconazole on 154 clinical and reference strains of Trichosporon asahii, Trichosporon asteroides, Trichosporon coremiiforme, Trichosporon faecale and Trichosporon inkin by using the EUCAST broth microdilution method (BMD) and Liofilchem MIC Test Strips (MTS).

METHODS

Antifungal susceptibility testing for isavuconazole, fluconazole, voriconazole and posaconazole was assessed by EUCAST E.DEF 7.3.2. MIC values of isavuconazole obtained by BMD after 48 h of incubation were compared with MTS MICs after 24 and 48 h of incubation.

RESULTS

T. asahii and T. asteroides showed the highest isavuconazole MIC90 values (0.5 mg/L). In clinical isolates, T. asahii exhibited the highest MIC90 values (0.5 mg/L) compared with non-T. asahii (0.06-0.25 mg/L). The five non-WT T. asahii isolates for fluconazole, voriconazole and posaconazole also exhibited high MICs of isavuconazole (≥0.5 mg/L). A better correlation between MTS and BMD MICs was observed after 24 h incubation for all species tested. MTS measurements performed at 48 h increased by at least 122% the number of isolates with >2 dilutions compared with the standard method.

CONCLUSIONS

Isavuconazole exhibited variable in vitro activity among the Trichosporon species tested, showing higher or equal MICs than the other azoles. The five non-WT T. asahii clinical isolates tested also exhibited high isavuconazole MICs, suggesting the occurrence of triazole cross-resistance. Our MTS data indicate that there is no advantage in extended reading time for MTS from 24 to 48 h for Trichosporon yeasts.

Current situation of endemic mycosis in the Americas and the Caribbean: Proceedings of the first international meeting on endemic mycoses of the Americas (IMEMA)

BACKGROUND

The Americas are home to biologically and clinically diverse endemic fungi, including Blastomyces, Coccidioides, Emergomyces, Histoplasma, Paracoccidioides and Sporothrix. In endemic areas with high risk of infection, these fungal pathogens represent an important public health problem.

OBJECTIVES

This report aims to summarise the main findings of the regional analysis carried out on the status of the endemic mycoses of the Americas, done at the first International Meeting on Endemic Mycoses of the Americas (IMEMA).

METHODS

A regional analysis for the Americas was done, the 27 territories were grouped into nine regions. A SWOT analysis was done.

RESULTS

All territories reported availability of microscopy. Seventy percent of territories reported antibody testing, 67% of territories reported availability of Histoplasma antigen testing. None of the territories reported the use of (1-3)-β-d-glucan. Fifty two percent of territories reported the availability of PCR testing in reference centres (mostly for histoplasmosis). Most of the territories reported access to medications such as trimethoprim-sulfamethoxazole, itraconazole, voriconazole and amphotericin B (AMB) deoxycholate. Many countries had limited access to liposomal formulation of AMB and newer azoles, such as posaconazole and isavuconazole. Surveillance of these fungal diseases was minimal.

CONCLUSIONS

A consensus emerged among meeting participants, this group concluded that endemic mycoses are neglected diseases, and due to their severity and lack of resources, the improvement of diagnosis, treatment and surveillance is needed.

P098 Human protothecosis: Acase report in Northeastern Brazil

Poster session 1, September 21, 2022, 12:30 PM - 1:30 PM

 

Introduction

Protothecosis is an emergent disease caused by members of the genus Prototheca. Most such infections probably occurred by traumática inoculation into subcutaneous tissues.

Objectives

It is to report a case of human cutaneous protothecosis identified in the state of Maranhão, northeast Brazil. Case report: 75-year-old patient, Merchant, from the municipality of São Luís Island, Northeastern Brazil. He sought care referring to an erythematous and painful lesion on the left arm that started 6 months before the treatment. On examination, he presented an infiltrative, hyperemic lesion with burning pain throughout the upper limb (Fig. 1). The patient reported that a week before the onset of the condition, he suffered trauma on the arm, with a laceration in the skin, while cleaning a sewage system with clay pipes. During the healing process, he noticed a hyperemic, slightly pruritic lesion measuring 2 cm which did not improve. He sought medical assistance at the dermatological service, who suspected dermatophytosis, initiating treatment with terbinafine (250 mg, once a day), evolving with worsening of the lesion. A lesion biopsy was indicated, to histopathological examination, which showed circular, moniliform structures, diagnosed as protothecosis (Fig. 2). Treatment with itraconazole (200 mg/day) was started, with no therapeutic response and the lesion spread throughout the patient's left upper limb. Submitted to a new investigation with biopsy for direct research and culture for fungi, being identified Prototheca Wicherhamii, by Maldi-Tof®, with sensitivity to itraconazole and ampfotericin B. PCR amplification of the genetic material obtained in the clinical isolate was performed with purification of its product, and sequencing showed genetic similarity of 97,46% with Prototheca Wickerhamii. The sequence obtained was deposited in Genbank under number MZ409514. In the absence of therapeutic response to itraconazole (400 mg/day), and significant worsening of the lesion, with presentation of a secondary infection caused by Staphylococcus haemoliticus, treatment with Clindamycin (900 mg/day for 10 days) and Liposomal Amphotericin B (4 mg/kg/day for 45 days) were performed. After suspension of Liposomal Amphotericin B, the lesions recurred in 15 days, and voriconazole (200 mg 12/12 h) was prescribed for 6 months, with complete regression of the lesions. Currently, he is free of injuries, having been followed up every 6 months.

Conclusion

Rare disease caused by chlorophyllous algae may be surprising due to the severity and lack of response to antifungals that show sensitivity in vitro.

P160 Paracoccidioidomycosis severe: Bizarre presentation in the face

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM

 

Introduction

Paracoccidioidomycosis is a systemic mycosis caused by the dimorphic fungus Paracoccidioides brasiliensis. The disease is restricted to Latin America. It is the principal systemic mycosis in Brazil, with higher incidences in the southern, southeastern and central regions.

Objectives

It's to report a case of paracoccioidomycosis with a bizarre presentation on the face.

Case Report

A 54-year-old male farmer from Açailândia, Maranhão, with a history of an extensive ulcerated lesion that started in the right wing of the nose. After 6 months of evolution, the lesion had already spread reaching the nasal and oral mucosa, evolving with acute respiratory failure, requiring tracheostomy (Fig.1). He was referred to the Cancer Hospital for a biopsy, which was referred for pathological examination, showing an intense inflammatory infiltrate consisting of lymphocytes, histiocytes, neutrophilis with giant, multinucleated cells that phagocytize refrigerant bodies, compatible with paracoccidioidomycosis. Material sent for direct examination and culture, showed positive for Paracoccidioides sp. After PCR amplification of the genetic material and sequencing, P. brasiliensis was identified. Chest tomography showed sparse ground-glass attenuation, but affecting both lungs and radiodense striations in the lower lobes bilaterally. Treatment was established with liposomal amphotericin B, with a good therapeutic response (Fig. 2). The patient was discharged from the hospital using itraconazole and still upper outpatient follow-up, with good healing of the lesions.

Conclusion

Paracoccidioidomycosis can get a severe presentation, distancing the physician from the diagnosis, showing that in all these situations, simple tests, such as the direct examination of lesional material or sputum can elucidate the diagnosis. We need to think about it in endemic area.

Epidemiology, clinical aspects, outcomes and prognostic factors associated with Trichosporon fungaemia: results of an international multicentre study carried out at 23 medical centres

BACKGROUND

Trichosporon fungaemia (TF) episodes have increased in recent years and mortality rates remain high despite the advances in the management of sepsis. New concepts about its clinical course, treatment and microbiology need to be investigated for the better management of this infection.

OBJECTIVES

To describe the aetiology, natural history, clinical management and prognostic factors of TF.

METHODS

TF episodes documented between 2005 and 2018 in 23 South American centres were retrospectively investigated by using a standard clinical form. Molecular identification, antifungal susceptibility testing and biofilm production were also performed.

RESULTS

Eighty-eight TF episodes were studied. Patients had several underlying conditions, including haematological diseases (47.7%), post-operative status (34%), solid organ transplants (n = 7, 7.9%), among others. Seventy-three (82.9%) patients had a central venous catheter (CVC) at TF diagnosis. The 30 day mortality rate was 51.1%. Voriconazole-based therapy was given to 34 patients (38.6%), with a 30 day mortality rate of 38.2%. Multivariate predictors of 30 day mortality were age (OR 1.036), mechanical ventilation (OR 8.25) and persistent neutropenia (OR 9.299). CVC removal was associated with over 75% decreased risk of 30 day mortality (OR 0.241). Microbiological analyses revealed that 77.7% of the strains were identified as Trichosporon asahii, and voriconazole showed the strongest in vitro activity against Trichosporon spp. Most of the strains (63%) were considered medium or high biofilm producers.

CONCLUSIONS

Older age, mechanical ventilation and persistent neutropenia were associated with poor prognosis. CVC may play a role in the pathogenicity of TF and its removal was associated with a better prognosis.

First case of SARS-COV-2 sequencing in cerebrospinal fluid of a patient with suspected demyelinating disease

The association between coronaviruses and central nervous system (CNS) demyelinating lesions has been previously shown. However, no case has been described of an association between the novel coronavirus (SARS-COV-2) and CNS demyelinating disease so far. SARS-COV-2 was previously detected in cerebrospinal fluid (CSF) sample of a patient with encephalitis. However, the virus identity was not confirmed by deep sequencing of SARS-COV-2 detected in the CSF. Here, we report a case of a patient with mild respiratory symptoms and neurological manifestations compatible with clinically isolated syndrome. The viral genome of SARS-COV-2 was detected and sequenced in CSF with 99.74-100% similarity between the patient virus and worldwide sequences. This report suggests a possible association of SARS-COV-2 infection with neurological symptoms of demyelinating disease, even in the absence of relevant upper respiratory tract infection signs.

Influence of epidemiology, immunosuppressive regimens, clinical presentation, and treatment on kidney transplant outcomes of patients diagnosed with tuberculosis: A retrospective cohort analysis

Tuberculosis (TB) mortality is high among kidney transplant (KT) recipients. Although local epidemiology is an important factor, diagnostic/therapeutic challenges and immunosuppressive therapy (ISS) may influence outcomes. We analyzed the cumulative incidence (CumI) of TB in KT recipients receiving a variety of ISS with long-term follow-up. Our retrospective single-center cohort study included all KT procedures performed between January 1, 1998, and August 31, 2014, with follow-up until August 31, 2014. Induction therapy was based on perceived immunological risk; maintenance ISS included prednisone and calcineurin inhibitor (CNI) plus azathioprine (AZA), and mycophenolic acid (MPA) or mechanistic target of rapamycin inhibitor (mTORi). Thirty-four patients received belatacept/MPA. KT was performed on 11 453 patients and followed for 1989 (IQR 932 to 3632) days. Among these, 152 patients were diagnosed with TB (CumI 1.32%). Median time from KT to TB was 18.8 (IQR 7.2 to 60) months, with 59% of patients diagnosed after the first year. Unadjusted analysis revealed an increasing confidence interval (CI) of TB (0.94% CNI/AZA vs 1.6% CNI/MPA [HR = 1.62, 95% CI = 1.13 to 2.34, P = .009] vs 2.85% CNI/mTORi [HR = 2.45, 95% CI = 1.49 to 4.32, P < .001] vs 14.7% belatacept/MPA [HR = 13.14, 95% CI = 5.27 to 32.79, P < .001]). Thirty-seven (24%) patients died, and 39 (25.6%) patients experienced graft loss. Cytomegalovirus infection (P = .02) and definitive ISS discontinuation (P < .001) were associated with death. Rejection (P = .018) and ISS discontinuation (P = .005) occurred with graft loss. TB occurred at any time after KT and was influenced by ISS.

Genetic diversity of Pneumocystis jirovecii from a cluster of cases of pneumonia in renal transplant patients: Cross-sectional study

Pneumocystis jirovecii can cause severe potentially life-threatening pneumonia (PCP) in kidney transplant patients. Prophylaxis of patients against PCP in this setting is usually performed during 6 months after transplantation. The aim of this study is to describe the molecular epidemiology of a cluster of PCP in renal transplant recipients in Brazil. Renal transplant patients who developed PCP between May and December 2011 had their formalin-fixed paraffin-embedded (FFPE) lung biopsy samples analysed. Pneumocystis jirovecii 23S mitochondrial large subunit of ribosomal RNA (23S mtLSU-rRNA), 26S rRNA, and dihydropteroate synthase (DHPS) genes were amplified by polymerase chain reaction (PCR), sequenced, and analysed for genetic variation. During the study period, 17 patients developed PCP (only four infections were documented within the first year after transplantation) and six (35.3%) died. Thirty FFPE samples from 11 patients, including one external control HIV-infected patient, had fungal DNA successfully extracted for further amplification and sequencing for all three genes. A total of five genotypes were identified among the 10 infected patients. Of note, four patients were infected by more than one genotype and seven patients were infected by the same genotype. DNA extracted from FFPE samples can be used for genotyping; this approach allowed us to demonstrate that multiple P. jirovecii strains were responsible for this cluster, and one genotype was found infecting seven patients. The knowledge of the causative agents of PCP may help to develop new initiatives for control and prevention of PCP among patients undergoing renal transplant and improve routine PCP prophylaxis.

Fatal case of donor-derived colistin-resistant carbapenemase-producing Klebsiella pneumoniae transmission in cardiac transplantation

Herein we report a fatal case of donor-derived transmission of XDR-resistant carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) in cardiac transplantation. A 59-year-old male patient with non-obstructive hypertrophic cardiomyopathy underwent heart transplantation. On day 5 post-operation, blood cultures from the donor were positive for colistin-resistant carbapenemase-producing K. pneumoniae (ColR KPC-Kp) susceptible only to amikacin. Recipient blood cultures were also positive for ColR KPC-Kp with the same sensitivity profile as the donor isolate with an identical PFGE pattern. The patient was treated with double-carbapenems and amikacin. The patient evolved to pericarditis, osteomyelitis, and pulmonary necrosis, all fragment cultures positive for the same agent. The patient developed septic shock, multiple organ failure and died on day 50 post-transplantation. Based on current microbiological scenario worldwide the possibility of transmitting multidrug resistant (MDR) organisms should be considered.

Melanized fungal infections in kidney transplant recipients: contributions to optimize clinical management

OBJECTIVES

This is a retrospective and observational study addressing clinical and therapeutic aspects of melanized fungal infections in kidney transplant recipients.

METHODS

We retrospectively reviewed medical records of all patients admitted between January 1996 and December 2013 in a single institution who developed infections by melanized fungi.

RESULTS

We reported on 56 patients aged between 30 and 74 years with phaeohyphomycosis or chromoblastomycosis (0.54 cases per 100 kidney transplants). The median time to diagnosis post-transplant was 31.2 months. Thirty-four (60.8%) infections were reported in deceased donor recipients. Fifty-one cases of phaeohyphomycosis were restricted to subcutaneous tissues, followed by two cases with pneumonia and one with brain involvement. Most dermatological lesions were represented by cysts (23/51; 45.1%) or nodules (9/51; 17.9%). Exophiala spp. (34.2%) followed by Alternaria spp. (7.9%) were the most frequent pathogens. Graft loss and death occurred in two patients and one patient, respectively. Regarding episodes of subcutaneous phaeohyphomycosis, a complete surgical excision without antifungal therapy was possible in 21 of 51 (41.2%) patients. Long periods of itraconazole were required to treat the other 30 (58.8%) episodes of subcutaneous disease. All four cases of chromoblastomycosis were treated only with antifungal therapy.

CONCLUSIONS

Melanized fungal infections should be considered in the differential diagnosis of all chronic skin lesions in transplant recipients. It is suggested that the impact of these infections on graft function and mortality is low. The reduction in immunosuppression should be limited to severely ill patients.