Pulmonary Mucormycosis due to Lichtheimia ramosa in a Patient with HIV Infection

A new terrein dimer and a new meroterpene from the mangrove endophytic fungus Lichtheimia sp

A new terrein dimer named lichtheicol A (1) and a new meroterpene named lichtheiterpene A (2), were isolated from the mangrove endophytic fungus Lichtheimia sp. J2B1, together with 10 known compounds (3-12). The planar structures and absolute configurations of 1 and 2 were established by a combination of extensive spectroscopic data analyses and electronic circular dichroism (ECD) calculations. Compounds 4 and 5 exhibited marked inhibitory effects against butyrylcholinesterase (BuChE) with IC50 values of 0.71 and 0.53 μM, respectively.

Mucormycosis in Human Immunodeficiency Virus-Infected Individuals: A Systematic Review of Case Reports

Mucormycosis in human immunodeficiency virus (HIV) infection is uncommon; notably, many cases have additional predisposing factors. Whether mucormycosis differs in HIV-affected individuals with and without additional risk factors (e.g., neutropenia, diabetes mellitus, and transplantation) remains unclear. In this systematic review, we identified 94 cases of HIV and mucormycosis classifiable into three groups: (1) HIV with additional risk factors (n = 50), (2) intravenous drug users (IVDU, n = 24), and (3) no other risk factor (n = 19) for mucormycosis. The most common presentation in IVDU was renal (41.7%) and cerebral mucormycosis (39.2%), whereas rhino-orbital mucormycosis (ROM, 4.2%) was uncommon. In the other two groups, ROM was the most common presentation. Rhizopus was the most frequently isolated Mucorales; however, in IVDU, Lichtheimia was the most common. The overall mortality was 53% and not significantly different in the three groups. Mucormycosis in HIV-infected individuals is rare without additional risk factors or IVDU.

Case report: The clinical utility of metagenomic next-generation sequencing in mucormycosis diagnosis caused by fatal Lichtheimia ramosa infection in pediatric neuroblastoma

Lichtheimia ramosa (L. ramosa) is an opportunistic fungal pathogen of the order Mucorales that may result in a rare but serious mucormycosis infection. Mucormycosis could be angioinvasive, causing thrombosis and necrosis in the nose, brain, digestive tract, and respiratory tract. The infection is highly lethal, especially in immunocompromised hosts, and the incidence has been on the rise. However, due to its relatively low incidence in pediatric population and the challenges with diagnosis, the awareness and management experience for pediatric mucormycosis are extremely limited, which might lead to poor outcomes. In this study, we comprehensively reviewed the course of a fatal rhinocerebral mucormycosis case in a pediatric neuroblastoma patient receiving chemotherapy. Due to a lack of awareness of the infection, the standard care of amphotericin B treatment was delayed and not administered until the identification of L. ramosa by metagenomic next-generation sequencing (mNGS)-based pan-pathogen detection of the patient's peripheral blood sample. We also reviewed the literature on L. ramosa infection cases reported worldwide between 2010 and 2022, with an analysis of clinical manifestation, prognosis, and epidemiological data. Our study not only highlighted the clinical value of comprehensive mNGS in rapid pathogen detection but also raised awareness of recognizing lethal fungal infection early in immunocompromised hosts including pediatric cancer patients.

Opportunistic Infections Among Human Immunodeficiency Virus (HIV) Infected Patients in Turkey: A Systematic Review

This study aimed to identify opportunistic infections among human immunodeficiency virus (HIV) infected patients in Turkey. Therefore, we conducted a systematic literature review of the studies published up to October 1, 2022, in the Pubmed, Web of Science (WoS), and ULAKBİM TR Dizin databases. We searched for medical subject headings (MeSH) terms of (HIV) OR (AIDS) OR (human immunodeficiency virus) AND (opportunistic infections) AND (Turkey). Fifty-five studies in Pubmed, 68 in WoS, and 212 in ULAKBİM TR Dizin were listed with these keywords. After removing duplicated studies, we included 22 original articles, two poster presentations, one short communication, one letter to the editor, and 17 case reports/series. Out of 1582 patients, we defined 788 patients (49.8%) as late presenters. In addition, we detected tuberculosis (286, 5.5%), candidal infections (207, 4%), and Pneumocystis jirovecii pneumonia (PCP) (113, 2.1%) as the most frequent opportunistic infections. According to our analysis, late presentation is a major problem in our country, and more screening and sensitization campaigns should be carried out to ensure early diagnosis and earlier care of patients.

Case report: A rare case of pulmonary mucormycosis caused by Lichtheimia ramosa in pediatric acute lymphoblastic leukemia and review of Lichtheimia infections in leukemia

Mucormycosis caused by Lichtheimia ramosa is an emerging and uncommon opportunistic infection in patients with hematological malignancies, with high mortality rates. Herein, we first report a case of pulmonary mucormycosis with Lichtheimia ramosa in a 3-year-old girl recently diagnosed with B-cell acute lymphoblastic leukemia. The diagnosis was made using computerized tomography of the lung, metagenomic next-generation sequencing (mNGS) of blood and sputum specimens, and microscopic examination to detect the development of Lichtheimia ramosa on the surgical specimen. She was effectively treated after receiving prompt treatment with amphotericin B and posaconazole, followed by aggressive surgical debridement. In our case, the fungal isolates were identified as Lichtheimia ramosa using mNGS, which assisted clinicians in quickly and accurately diagnosing and initiating early intensive treatment. This case also indicated the importance of strong clinical suspicion, as well as aggressive antifungal therapy combined with surgical debridement of affected tissues.

Risk Assessment for Molds in the Vicinity of a Child Requiring Peritoneal Dialysis Living in a Rural Northern German Area

As well as severe immunosuppression, other predisposing factors may facilitate invasive mycosis caused by molds. Chronic kidney disease and the resulting peritoneal dialysis have been reported as factors putting patients at risk of fungal infections from environmental sources. We describe an environmental investigation undertaken to guide exposure prevention for a peritoneal dialysis patient with transient colonization of her nostrils by Lichtheimia corymbifera in a rural area of northern Germany. Systematic screening for airborne and surface-deposited molds enabled targeted recommendations to be made, although Lichtheimia corymbifera itself was not grown from the collected environmental samples. This communication is intended to illustrate how such an investigation can be performed on the basis of the environmental distribution of the molds and how preventive recommendations can be derived from the results.

Identification of Fungal Species and Detection of Azole-Resistance Mutations in the Aspergillus fumigatus cyp51A Gene at a South Korean Hospital

PURPOSE

With changing fungal epidemiology and azole resistance in Aspergillus species, identifying fungal species and susceptibility patterns is crucial to the management of aspergillosis and mucormycosis. The objectives of this study were to evaluate performance of panfungal polymerase chain reaction (PCR) assays on formalin-fixed paraffin embedded (FFPE) samples in the identification of fungal species and in the detection of azole-resistance mutations in the Aspergillus fumigatus cyp51A gene at a South Korean hospital.

MATERIALS AND METHODS

A total of 75 FFPE specimens with a histopathological diagnosis of aspergillosis or mucormycosis were identified during the 10-year study period (2006-2015). After deparaffinization and DNA extraction, panfungal PCR assays were conducted on FFPE samples for fungal species identification. The identified fungal species were compared with histopathological diagnosis. On samples identified as A. fumigatus, sequencing to identify frequent mutations in the cyp51A gene [tandem repeat 46 (TR46), L98H, and M220 alterations] that confer azole resistance was performed.

RESULTS

Specific fungal DNA was identified in 31 (41.3%) FFPE samples, and of these, 16 samples of specific fungal DNA were in accord with a histopathological diagnosis of aspergillosis or mucormycosis; 15 samples had discordant histopathology and PCR results. No azole-mediating cyp51A gene mutation was noted among nine cases of aspergillosis. Moreover, no cyp51A mutations were identified among three cases with history of prior azole use.

CONCLUSION

Panfungal PCR assay with FFPE samples may provide additional information of use to fungal species identification. No azole-resistance mediating mutations in the A. fumigatus cyp51A gene were identified among FFPE samples during study period.

First Case of Rhinocerebral Mucormycosis Caused by Lichtheimia ornata, with a Review of Lichtheimia Infections

BACKGROUND

Lichtheimia species are emerging opportunistic fungal pathogens in the Mucorales, causing serious skin and respiratory infections in immunocompromised patients. Established agents are Lichtheimia corymbifera and L. ramosa, while L. ornata is a novel agent. Available data on a species-specific analysis of Lichtheimia infections are limited.

METHODS

The first case of a fatal rhino-orbital-cerebral infection in a hematopoietic stem cell transplantation recipient caused by L. ornata is reported; the agent was identified by sequencing the ITS ribosomal region. We reviewed the literature on mucormycosis due to Lichtheimia species between 2009 and 2018, with an analysis of risk factors and epidemiological and clinical data.

RESULTS

In addition to our Lichtheimia ornata case, 44 cases of human Lichtheimia were analyzed. Lichtheimia predominated in Europe (68.2%), followed by Asia (16%), and Africa (9%). The most common underlying condition was hematological malignancy (36.3%), followed by trauma/major surgery (27.3%), while diabetes mellitus was rare (11.4%). Site of infection was mostly skin and soft tissues (45.5%) and lung (25%), while relatively few cases were disseminated (13.6%) or rhinocerebral (11.4%). Mortality (36.4%) was mainly due to disseminated and rhinocerebral infections.

CONCLUSION

In contrast to Rhizopus, the most common agent of mucormycosis recorded in patients with diabetes mellitus, Lichtheimia infections were primarily associated with hematological malignancies and major skin barrier damage. Given the fact that classical rhinocerebral mucormycosis remains difficult to treat, independent of causative species, timely application of amphotericin B accessory to debridement may be required for patient survival.

A Rare Case of Pulmonary Coinfection by Lichtheimia ramosa and Aspergillus fumigatus in a Patient With Delayed Graft Function After Renal Transplantation

Pulmonary coinfection with Mucor and Aspergillus species has not been reported in organ transplant recipients. Here, we report a rare case of pulmonary coinfection with invasive fungal species in a renal transplant recipient with delayed graft function. The patient was first treated with a regime containing voriconazole, but the infection only worsened. Then, bronchoalveolar lavage fluid culture and internal transcribed spacer region sequencing were performed, and simultaneous pulmonary infection by Lichtheimia ramosa and Aspergillus fumigatus was clearly diagnosed. Susceptibility testing determined that the fungi were sensitive to amphotericin B and posaconazole. Therefore, a therapeutic regime containing posaconazole and amphotericin B liposome, which are less toxic to the kidney, was planned and resulted in resolution of the infectious symptoms. The present case demonstrates the importance of identifying fungal pathogens early and definitively, determining the effective anti-fungal medications, and administering the properly planned therapeutic regime in a timely manner to treat cases of coinfection in transplant recipients.

Comparative analysis of nonvolatile and volatile metabolites in Lichtheimia ramosa cultivated in different growth media

Lichtheimia ramosa is one of the predominant filamentous fungi in Korean traditional nuruk. The nonvolatile and volatile metabolites of L. ramosa cultivated in three growth media: complete medium (CM), potato dextrose broth (PDB), and sabouraud dextrose broth (SDB), were investigated and compared. Among nonvolatile metabolites, serine, lysine, and ornithine increased in CM and PDB cultivated with L. ramosa during the exponential phase. In addition, glucose level increased in CM whereas decreased in PDB and SDB. The major volatile metabolites in the extract samples were acetic acid, ethanol, 3-methyl-2-buten-1-ol, 2-phenylethanol, ethylacetate, 2-furaldehyde, 5-(hydroxymethyl)-2-furaldehyde, 2,3-dihydro-3,5,-dihydroxy-6-methyl-4H-pyran-4-one, and α-humulene. In particular, the levels of volatile metabolites related to makgeolli (e.g., acetic acid, ethanol, and ethyl acetate) were highest in extracts cultivated in CM. On the other hand, the level of 2-phenylethanol was relatively higher in PDB and SDB, possibly due to there being more phenylalanine present in the biomass sample in media.

Cutaneous mucormycosis in advanced HIV disease

Angionvasive mucormycosis is an emerging fungal disease known to affect mainly diabetics or subjects with profound neutropenia. Infection usually occurs through the inhalation route, but cutaneous inoculation may occur after trauma or burns. However, mucormycosis remains unusual in HIV infection. We report a fatal case of cutaneous mucormycosis due to Rhizopus arrhizus involving the scalp following herpes zoster infection. The patient was a 42-year-old man with advanced AIDS failing on salvage antiretroviral therapy. The fungus was diagnosed on the basis of histopathology and culture. Our case emphasizes the need to consider mucormycosis in the differential diagnosis of necrotic cutaneous lesions in patients with late-stage HIV disease.

The burden of mucormycosis in HIV-infected patients: A systematic review

OBJECTIVES

Mucormycosis is an invasive fungal infection afflicting immunocompromised patients, causing a significant degree of morbidity and mortality. The purpose of the study was to provide a comprehensive analysis describing the epidemiology and outcome of mucormycosis in the scenario of HIV infection.

METHODS

We systematically searched PubMed for reports about mucormycosis associated with HIV. Eligible studies describe the predisposing factor, clinical form, treatment, and survival outcome.

RESULTS

We included 61 articles from 212 reviewed abstracts, corresponding to 67 cases. Patients were mostly men (68.2%) with a median CD4(+) count of 47 [IQR 17-100] cells/mm(3). Intravenous drug use (50%), neutropenia (29.7%) and corticosteroid use (25%) were the predominant associated factors. The main clinical forms were disseminated (20.9%), renal (19.4%), and rhino-cerebral (17.9%). Rhizopus (45.5%) and Lichtheimia spp (30.3%) were the main fungal isolates. Treatment consisted of antifungal therapy and surgery in 38.8%. Overall mortality rate was 52.2%, and varied with the site of infection: 92.9% for disseminated disease, 62.5% for cerebral disease, 60% for pulmonary infection, and 36.4% for cutaneous infection. Survival was worse for those who did not initiate antifungals (p = .04), who were antiretroviral naïve (p = .01), who were admitted to ICU (p = .003) or had disseminated disease (p = .007).

CONCLUSIONS

Mucormycosis is a life-threatening infection in HIV patients and clinician should be aware of this co-infection in the differential diagnosis of HIV opportunistic infections.

Lichtheimia ramosa: A Fatal Case of Mucormycosis

Mucormycosis due to Lichtheimia ramosa is an infrequent opportunistic infection that can potentially be angioinvasive when affecting inmunocompromised hosts. We present a fatal case of mucormycosis, affecting a 56-year-old male with diabetes mellitus and siderosis, initially admitted to our hospital due to an H1N1 infection. The subject's clinical condition worsened and he finally died because of a necrotizing bilateral pneumonia with disseminated mycotic thromboses due to Lichtheimia ramosa, which is an emerging Mucoralean fungus. This is an infrequent case because of the extent to which it affected a subject without overt immunocompromise. This case underlines the importance of an early premortem diagnosis and treatment in order to prevent rapid progression of this disease, as well as the need of considering mucormycosis when facing subjects with multiple emboli and fever unresponsive to usual antimicrobials.

The genome sequence of four isolates from the family Lichtheimiaceae

This study reports the release of draft genome sequences of two isolates of Lichtheimia corymbifera and two isolates of L. ramosa. Phylogenetic analyses indicate that the two L. corymbifera strains (CDC-B2541 and 008-049) are closely related to the previously sequenced L. corymbifera isolate (FSU 9682) while our two L. ramosa strains CDC-B5399 and CDC-B5792 cluster apart from them. These genome sequences will further the understanding of intraspecies and interspecies genetic variation within the Mucoraceae family of pathogenic fungi.

De Novo Whole-Genome Sequence and Genome Annotation of Lichtheimia ramosa

We report the annotated draft genome sequence of Lichtheimia ramosa (JMRC FSU:6197). It has been reported to be a causative organism of mucormycosis, a rare but rapidly progressive infection in immunocompromised humans. The functionally annotated genomic sequence consists of 74 scaffolds with a total number of 11,510 genes.