La infección fúngica en el paciente pediátrico inmunodeprimido

In recent years, immunodeficiency condition has experienced a rise among children, who are at risk of invasive fungal infections (IFI) due to their health condition. Cancer, non-malignant hematological diseases, as primary immunodeficiencies, hematopoietic stem cell transplantation (HSCT), extreme prematurity, or critically ill condition in Pediatric Intensive Care Unit (PICU) are some immunosuppressive situations in children. The use of oncologic therapies, including immunotherapy and monoclonal antibodies, for the treatment of the aforementioned health conditions has led to an increase in morbidity and mortality rates of IFI in children.The underlying diseases and their management, comorbidities, the diagnostic tests used (both molecular and imaging), as well as the treatment used can be significantly different between adult patients and children admitted to PICU or with cancer. In pediatrics, the treatment of IFI is based primarily on pharmacokinetic studies performed in adults. In higher risk patients prophylaxis should be considered and, in the case of an IFI diagnosis, an antifungal treatment should be administered as early as possible, supported by the reversion of the immune dysfunction and surgery when appropriate.     

Evolución de la infección fúngica invasora en los últimos 30 años

Clinical mycology is in continuous development. The appearance of new clinical guidelines has made it possible to improve the approach to opportunistic fungal infections, especially in immunosuppressed patients (oncohematological and/or transplant recipients). At the same time, the development of new diagnostic tools and new antifungals with a greater spectrum of action and fewer side effects have led to faster diagnoses and treatments that are more effective. Along with these advances, there has been a change in the epidemiology of invasive fungal infection (IFI), with the appearance of new patients (e.g., COPD, liver cirrhosis, post-influenza) and new microorganisms (Candida auris, Lomentospora prolificans, mucorales), and resistant fungi (isolates of Aspergillus resistant to azoles) which the clinician must take into account when choosing the treatment of a patient with an IFI. In this paper we will briefly review the advances in recent decades and the emerging problems.     

Hierro e infección fúngica invasiva

Iron is an essential factor for both the growth and virulence of most of microorganisms. As a part of the innate (or nutritional) immune system, mammals have developed different mechanisms to store and transport this element in order to limit free iron bioavailability. To survive in this hostile environment, pathogenic fungi have specific uptake systems for host iron sources, one of the most important of which is based on the synthesis of siderophores-soluble, low-molecular-mass, high-affinity iron chelators. The increase in free iron that results from iron-overload conditions is a well-established risk factor for invasive fungal infection (IFI) such as mucormycosis or aspergillosis. Therefore, iron chelation may be an appealing therapeutic option for these infections. Nevertheless, deferoxamine –the first approved iron chelator– paradoxically increases the incidence of IFI, as it serves as a xeno-siderophore to Mucorales. On the contrary, the new oral iron chelators (deferiprone and deferasirox) have shown to exert a deleterious effect on fungal growth both in vitro and in animal models. The present review focuses on the role of iron metabolism in the pathogenesis of IFI and summarises the preclinical data, as well as the limited clinical experience so far, in the use of new iron chelators as treatment for mucormycosis and invasive aspergillosis.     

Tratamiento antifúngico individualizado en el paciente crítico con infección fúngica invasora

Invasive candidiasis (IC) is the most common invasive fungal infection (IFI) affecting critically ill patients, followed by invasive pulmonary aspergillosis (IPA). International guidelines provide different recommendations for a first-line antifungal therapy and, in most of them, echinocandins are considered the first-line treatment for IC, and triazoles are so for the treatment of IPA. However, liposomal amphotericin B (L-AmB) is still considered a second-line therapy for both clinical entities. Although in the last decade the management of IFI has improved, several controversies persist. The antifungal drugs currently available may have a suboptimal activity, or be wrongly used in certain IFI involving critically ill patients. The aim of this review is to analyze when to provide individualized antifungal therapy to critically ill patients suffering from IFI, emphasizing the role of L-AmB. Drug-drug interactions, the clinical status, infectious foci (peritoneal candidiasis is discussed), the fungal species involved, and the need of monitoring the concentration of the antifungal drug in the patient are considered.     

Relevancia de la anfotericina B liposomal en el tratamiento de las infecciones fúngicas invasoras en pacientes oncohematológicos

Liposomal amphotericin B (L-AmB) has been a key cornerstone for the management of invasive fungal infections (IFI) caused by a wide array of molds and yeasts during the last three decades. Multiple studies performed over this period have generated a large body of evidence on its efficacy and safety, becoming the main antifungal agent in the management of IFI in patients with hematologic malignancies in several not mutually exclusive clinical settings. First, L-AmB is the most commonly used antifungal agent in patients undergoing intensive chemotherapy for acute leukemia and high-risk myelodysplastic syndrome, as well as in hematopoietic stem cell transplant recipients. Additionally, due to the administration of newer targeted therapies (such as monoclonal antibodies or small molecule inhibitors), opportunistic mold infections are increasingly being reported in patients with hematologic malignancies usually considered low-risk for IFI. These agents usually have a high drug-drug interaction potential, being triazoles, commonly used for antifungal prophylaxis, included. Finally, patients developing breakthrough IFI because of either subtherapeutic concentrations of antifungal prophylactic drugs in blood or selection of resistant strains, require broad spectrum antifungal therapy, usually with an antifungal of a different class. In both situations, L-AmB remains as the best option for early antifungal therapy.     

Primer caso de infección fúngica invasora por Candida fabianii en un paciente pediátrico no neonatal

BackgroundInvasive fungal diseases have increased in recent years. Candida species are the most common aetiology. Candida albicans, Candida parapsilosis, Candida tropicalis, Candida glabrata and Candida krusei are the cause of most of them. The aim of this work is to describe the first isolation of Candida fabianii in the blood of a non-neonatal paediatric patient.Case reportA 2 year-old male with short bowel syndrome, severe malnutrition, and hypophosphataemic rickets deficiency was admitted to paediatric intensive care due to a respiratory tract infection and suspicion of an intestinal pseudo-obstruction. He received several cycles of broad-spectrum antibiotics for several infections due to Pseudomonas aeruginosa and Escherichia coli. After the surgical correction of the intestinal disorder he suffered a new episode of sepsis where yeasts were isolated by culture. The species identification was performed by means of mass spectrometry (MALDI-TOF system, Bruker Daltonic). The identity of the isolate was C. fabianii (anamorph)/Pichia fabianii (teleomorph) with a score of 2.149. Antifungal treatment with caspofungin was prescribed, with good progress of the patient.ConclusionsMolecular techniques are important for the identification of these species, although mass spectrometry offered a reliable and rapid diagnosis. Treatment with caspofungin was effective.     

Infección múltiple fúngica en un paciente diabético

BackgroundMixed fungal infections although undervalued, are more common than mentioned in the scientific literature. These infections have a poor prognosis for the patient.ObjectivesWe present an unusual case of a 61-year-old diabetic male who had a rhino-orbito-sinusal zygomycosis in 2001. After surgical debridement of the infected parts, along with antifungal therapy with liposomal amphotericin B, the patient started improving. Several years later the patient was hospitalized due to a similar problem and was diagnosed of rhino-orbito-cerebral zygomycosis.MethodsIn both episodes, a histopathological examination and cultures were performed on the sinus lesions. Tissue sections were stained with haematoxylin and eosin, Giemsa, periodic acid-Schiff (PAS) and Grocott's methenamine silver, and cultures specific for fungi were performed.ResultsThe histopathology studies revealed the presence of bacteria, actinomyces and a mixed infection by at least four different fungi, all of them well differentiated by their morphology. Despite the rapid diagnosis the patient died due to spreading to the central nervous system.ConclusionsMixed infections by fungi are rare, but due to the high incidence of immunodeficiencies they could occur more often than reported. We would like to alert on the possibility of acquired mixed infection by fungi which have shown to be high aggressive and have a worse prognostic in patients with underlying diseases.     

Estado actual de la histoplasmosis diseminada progresiva en pacientes con infección por el VIH en un hospital de tercer nivel en Perú

BackgroundProgressive disseminated histoplasmosis (PDH) is an endemic disease in most of Latin America, especially among patients with HIV. There are few reports about this disease in Peru.AimsTo describe the clinical, epidemiological and mycological features of patients with PDH and HIV evaluated in a tertiary hospital.MethodsA retrospective study to find out the data of patients diagnosed with PDH and HIV in the period 2000–2019 was carried out. For the statistical analysis of quantitative variables, measures of central tendency and dispersion were used; for the qualitative variables, absolute and relative frequencies were used.ResultsForty-three male patients with PDH were diagnosed in the study period, with a median age of 33 years (IQR: 29–38 years) and a median CD₄ lymphocytes count of 39 cells/mm³ (IQR: 20–83 cells/mm³). Eighty six percent of the patients were born or had travelled to the jungle, 58.1% were alcohol users and 16.1% had a history of pulmonary tuberculosis. When compared to histopathology, the culture had a better sensitivity to achieve a diagnosis (p < 0.05).ConclusionsPeruvian patients with PDH and HIV infection were mainly young male adults that were born or had travelled to the jungle, with a CD₄ count below 100 cells/mm³. In patients with the described characteristics it would be advisable to check for PDH. Implementing rapid diagnostic tests is also necessary.     

Farmacología de los antifúngicos en el tratamiento de la aspergilosis

The treatment of invasive aspergillosis requires the use of drugs that characteristically have complex pharmacokinetic properties, the knowledge of which is essential to achieve maximum efficacy with minimal risk to the patient. The lipid-based amphotericin B formulations vary significantly in their pharmacokinetic behaviour, with very high plasma concentrations of the liposomal form, probably related to the presence of cholesterol in their structure. Azoles have a variable absorption profile, particularly in the case of itraconazole and posaconazole, with the latter very dependent on multiple factors. This may also lead to variations in voriconazole, which requires considering the possibility of monitoring plasma concentrations.The aim of this article is to review some of the most relevant aspects of the pharmacology of the antifungals used in the prophylaxis and treatment of the Aspergillus infection. For this reason, it includes the most relevant features of some of the azoles normally prescribed in this infection (itraconazole, posaconazole and voriconazole) and the amphotericin B formulations.     

Nuevas perspectivas en el tratamiento farmacológico de la enfermedad de Cushing

Hypercortisolism induced by Cushing disease causes high morbidity and mortality.The treatment of choice is pituitary surgery, but it often fails to achieve cure, and other treatment modalities (radiotherapy, bilateral adrenalectomy) may therefore be required. If these treatments are not effective or while waiting for their results, hypercortisolism should be controlled with drugs.The classical drug treatments are those that act by inhibiting cortisol secretion by the adrenal gland (ketoconazole, metyrapone, mitotane, etomidate).The preliminary results of a new drug (LCI699) which is a potent enzyme inhibitor of cortisol secretion have been reported.A clinical trial of the safety and efficacy of mifepristone, a glucocorticoid receptor antagonist, has just been published.The drugs deserving more attention today are those with a direct action on the tumor by inhibiting ACTH secretion: somatostatin analogues (pasireotide), dopamine agonists (cabergoline), PPAR-γ, and retinoic acid.A special review is made of the available clinical trials with pasireotide and cabergoline.     

Procedimientos endoluminales/endoscópicos en el tratamiento de la obesidad

Few effective therapeutic tools are currently available to fight the increasing prevalence of obesity and its associated comorbidities. Bariatric surgery is the only treatment with proven long-term effectiveness, but is associated to a high surgical risk and significant economic costs because of its technical complexity and the characteristics of patients. This is leading to development of new endoscopic procedures with less clinical risks and economic costs, while maintaining the benefits in terms of morbidity and mortality, which could even serve as a bridging element before surgery in cases where this is unavoidable, allowing for preoperative weight loss and control of comorbidities in order to improve anesthetic risks and possible complications. The purpose of this review was to analyze the most relevant and promising endoscopic techniques currently available.     

Particularidades clínicas del paciente crítico con infección fúngica invasora

BackgroundInvasive fungal infection (IFI) is an entity that encompasses different types of infections caused by different types of those fungi pathogenic for humans. In the setting of critically ill patients with multiple and oftenconcurrent risk factors and comorbidities the most common are those caused by the Candida and Aspergillus species. Among the characteristics of IFI in critically ill patients, three aspects can be highlighted: those related to the host (e.g.: risk factors, clinical severity), those related with the pathogen (sensitivity, virulence), or those concerning antifungal treatment (spectrum, features PK / PD, safety, interactions). The fungus that most often causes an IFI in critically ill patients is Candida; the most common type infections are candidemia, Candida peritonitis and catheter-related infections. In recent years new antifungal treatments have expanded the therapeutic options, with echinocandins as a clear choice, often the first in the latest guidelines in critically ill patients with IFI.Case reportWe report the case of a critically ill patient having the most common risk factors, multiple organ dysfunction and development of an IFI. The complexity of establishing an antifungal treatment from the moment of its inception, its setting, and the considerations of the different therapeutic possibilities according to organ dysfunction of the patient are discussed. The antifungal treatment options mentioned in the current guidelines and recommendations are also evaluated.ConclusionsThe most common fungal infection in critically ill patients is invasive candidiasis, with candidemia or candida peritonitis being the most frequent clinical presentations. Candins have brought new possibilities for treating these complex patients due to their good safety profile and clinical efficacy.     

Actualización sobre infección por Clostridium difficile en el paciente mayor

Clostridium difficile infection is the most common cause of health care-associated diarrhoea, and its incidence increases with age. Clinical challenges, risk of resistance to treatment, risk of recurrence, and treatment responses are different in elderly.The aim of this review is to discuss the updated epidemiology, pathophysiology, diagnosis, and therapeutic management of C. difficile infection in elderly with the available data.     

Utilidad clínica de la micafungina en el tratamiento de las candidiasis invasoras en el paciente oncohematológico

BackgroundInvasive candidiasis is a severe infection among onco-hematological patients, with an attributable mortality around 40%. Micafungin has shown efficacy in antifungal prophylaxis among hematopoietic stem cell transplant recipients and in the treatment of esophageal candidiasis.AimsTo assess the role of micafungin in the treatment of invasive candidiasis among onco-hematological patients.MethodsLiterature review.ResultsIn a study on 126 patients with candidemia treated with micafungin, an overall response rate of 83% was reported. A double-blind study of 531 patients with invasive candidiasis comparing micafungin (100 mg/day) versus liposomal amphotericin B (3 mg/kg/day) reported success in 90% of patients in both arms, with a more favorable safety profile with micafungin. Other double blind randomized, phase III study compared two doses of micafungin (100 mg/day and 150 mg/day) with standard doses of caspofungin (70 mg loading dose, then 50 mg/day) in adults with invasive candidiasis. Overall success rate was 74% for micafungin 100 mg/day, 70% for micafungin 150 mg/day, and 71% for caspofungin. A double blind randomized study compared micafungin (2 mg/kg/day) to liposomal amphotericin B (3 mg/kg/day) in the treatment of invasive candidiasis in children with a predominance of infections with non-albicans Candida spp. Overall success rate was similar (73% for micafungin and 76% for liposomal amphotericin B).ConclusionsComparative phase III studies have demonstrated non-inferiority of micafungin compared to standard antifungal agents for invasive candidiasis. Micafungin is safe and effective in the treatment of children and adults with invasive candidiasis. Effectivity in invasive infections caused by non-albicans Candida spp is especially relevant in onco-hematological patients receiving fluconazole prophylaxis.