A Case of Acute Cerebral Aspergillosis Complicating Influenza A/H1N1pdm 2009

Impact of Surgical and Medical Treatment on Survival of Patients with Cerebral Aspergillosis: Systematic Review of the Literature

OBJECTIVE

Cerebral aspergillosis carries a high mortality. Rapid diagnosis and treatment can increase survival, but symptoms and imaging findings are nonspecific. The literature on cerebral aspergillosis consists mostly of case reports and case series and lacks large-scale review of data.

METHODS

We performed a review of the literature using PubMed in March 2019. We recorded the year of publication, age and sex of patients, neurosurgical involvement, the antifungals administered, use of intrathecal antifungals, and the outcome of patients. The relationships among variables were tested using bivariant statics and linear regression.

RESULTS

A total of 324 studies met the eligibility criteria, and 198 studies including 248 patients were included. Surgical resection (odds ratio [OR], 0.45; 95% confidence interval [CI], 0.25-0.80; P < 0.01) and administration of voriconazole (OR, 0.32; 95% CI, 0.18-0.55; P < 0.001) or itraconazole (OR, 0.36; 95% CI, 0.16-0.72; P < 0.001) were shown to be significantly associated with survival.

CONCLUSIONS

Given the significant survival benefits for patients who received voriconazole and surgical intervention, we suggest early antifungal medical treatment and resection.

It's all in your head: antifungal immunity in the brain

As the incidence rate of invasive fungal infections has increased with the use of modern medical interventions, so too has the occurrence of fungi invading the brain. Fungi such as Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus often infect immunocompromised individuals, and can use several strategies to invade the central nervous system (CNS) by penetrating the blood-brain barrier. Once in the brain parenchyma the specialized resident immune cells need to effectively recognize the fungus and mount an appropriate immune response to clear the infection, without causing debilitating immune-mediated toxicity and neuronal damage. Here we review the current knowledge pertaining to the antifungal response of the CNS and highlight areas where future research is required.

Invasive pulmonary aspergillosis complicating severe influenza: epidemiology, diagnosis and treatment

PURPOSE OF REVIEW

Bacterial super-infection of critically ill influenza patients is well known, but in recent years, more and more reports describe invasive aspergillosis as a frequent complication as well. This review summarizes the available literature on the association of invasive pulmonary aspergillosis (IPA) with severe influenza [influenza-associated aspergillosis (IAA)], including epidemiology, diagnostic approaches and treatment options.

RECENT FINDINGS

Though IPA typically develops in immunodeficient patients, non-classically immunocompromised patients such as critically ill influenza patients are at high-risk for IPA as well. The morbidity and mortality of IPA in these patients is high, and in the majority of them, the onset occurs early after ICU admission. At present, standard of care (SOC) consists of close follow-up of these critically ill influenza patients with high diagnostic awareness for IPA. As soon as there is clinical, mycological or radiological suspicion for IAA, antifungal azole-based therapy (e.g. voriconazole) is initiated, in combination with therapeutic drug monitoring (TDM). Antifungal treatment regimens should reflect local epidemiology of azole-resistant Aspergillus species and should be adjusted to clinical evolution. TDM is necessary as azoles like voriconazole are characterized by nonlinear pharmacokinetics, especially in critically ill patients.

SUMMARY

In light of the frequency, morbidity and mortality associated with influenza-associated aspergillosis in the ICU, a high awareness of the diagnosis and prompt initiation of antifungal therapy is required. Further studies are needed to evaluate the incidence of IAA in a prospective multicentric manner, to elucidate contributing host-derived factors to the pathogenesis of this super-infection, to further delineate the population at risk, and to identify the preferred diagnostic and management strategy, and also the role of prophylaxis.

TR34/L98H Mutation in CYP51A Gene in Aspergillus fumigatus Clinical Isolates During Posaconazole Prophylaxis: First Case in Korea

Azole resistance in Aspergillus fumigatus is an emerging problem, especially in immunocompromised patients. It has been reported worldwide, including in Asia, but has not yet been reported in Korea. Here, we report a case of invasive pulmonary aspergillosis (IPA) caused by azole-resistant A. fumigatus that developed in a hematopoietic stem cell transplantation recipient during posaconazole prophylaxis for immunosuppressive therapy of graft-versus-host diseases. We identified TR34/L98H/S297T/F495L mutation in the CYP51A gene of A. fumigatus clinical isolate obtained from bronchial washing fluid. Minimal inhibitory concentrations for itraconazole, voriconazole, and posaconazole were > 16, 1, and 4 μg/mL, respectively. While IPA improved partially under voriconazole treatment, the patient died from carbapenemase-producing Klebsiella pneumoniae bacteremia. Further epidemiological surveillance studies are warranted.

Invasive pulmonary aspergillosis and influenza co-infection in immunocompetent hosts: case reports and review of the literature

Invasive pulmonary aspergillosis (IPA) is classically considered an illness of severely immunocompromised patients with limited host defenses. However, IPA has been reported in immunocompetent but critically ill patients. This report describes two fatal cases of pathologically confirmed IPA in patients with influenza in the intensive care unit. One patient had influenza B infection, whereas the other had influenza A H1N1. Both patients died despite broad-spectrum antimicrobials, mechanical ventilation, and vasopressor support. Microscopic and histologic postmortem examination confirmed IPA. Review of the English language and foreign literature indicates that galactomannan antigen testing and classic radiologic findings for IPA may not be reliable in immunocompetent patients. Respiratory cultures which grow Aspergillus species in critically ill patients, particularly those with underlying influenza infection, should not necessarily be disregarded as contaminants or colonizers. Further research is needed to better understand the immunological relationship between influenza and IPA for improved prevention and treatment of influenza and Aspergillus co-infections.

Invasive Aspergillosis Associated With Severe Influenza Infections

Background. Invasive aspergillosis may occur in the setting of severe influenza infections due to viral-induced respiratory epithelium disruption and impaired immune effects, but data are limited.

Methods. A retrospective study was conducted among severe influenza cases requiring medical intensive care unit (ICU) admission at an academic center during the 2015–2016 season. Data collected included respiratory cultures, medical conditions and immunosuppressants, laboratory and radiographic data, and outcomes. A systematic literature review of published cases in the English language of aspergillosis complicating influenza was conducted.

Results. Six (75%) of 8 ICU influenza cases had Aspergillus isolated; 5 were classified as invasive disease. No ICU patient testing negative for influenza infection developed aspergillosis during the study period. Among cases with invasive aspergillosis, influenza infection was type A (H1N1) (n = 2) and influenza B (n = 3). Published and current cases yielded n = 57 (European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group criteria: 37% proven, 25% probable, and 39% possible cases). An increasing number of cases were reported since 2010. Sixty-five percent of cases lacked classic underlying conditions at admission for aspergillosis, 86% had lymphopenia, and 46% died.

Conclusions. Aspergillosis may occur in the setting of severe influenza infections even among immunocompetent hosts. Risks may include influenza A (H1N1) or B infections and viral-induced lymphopenia, although further studies are needed. Prompt diagnosis and antifungal therapy are recommended given high mortality rates.