Aspergillosis of bones and joints - a review from 2002 until today

Aspergilloma Superinfection in the Spinal Canal of an 18-Year-Old Man: A Case Report

CASE

An 18-year-old immunocompetent man presented with symptomatic lumbar canal stenosis, discharging sinuses, and cold abscess for 3 years treated with multiple incision drainage procedures with cottonoid packing antibiotic therapy. Radiographic imaging showed a soft tissue mass in the canal causing bony destruction. Postoperative histopathological examination showed an Aspergillus fungal ball. Patient showed improvement at 6-month follow-up with medical management.

CONCLUSION

As far as we know, this is the first case report showing an aspergilloma involving the vertebral column. Inadequate antibiotic treatment and blind introduction of a foreign body into sinus tracts can lead to fungal infections mimicking tuberculosis, causing disastrous outcomes. Fungal cultures are recommended routinely.

Aspergillus granulosus femoral osteomyelitis in a cardiac transplant patient: first reported case and literature review

Aspergillus osteomyelitis is a rare complication of extrapulmonary invasive aspergillosis, which usually presents as spondylodiscitis. The clinical picture is usually paucisymptomatic and of long evolution, which leads to diagnostic difficulties, especially in immunosuppressed patients presenting a delayed systemic host response. We report a case of femoral osteomyelitis caused by Aspergillus granulosus in a heart transplant recipient successfully treated with a combined surgical and antifungal approach. A 65-year-old heart transplant male presented with left knee pain lasting 3 months. X-ray and magnetic resonance imaging identified a lesion with aggressive characteristics at the distal third of the left femur, due to which the patient underwent excisional surgery. Aspergillus granulosus was cultured from the removed material and antifungal treatment with oral isavuconazole was started. Chest imaging excluded pulmonary aspergillosis, while the positron emission tomography/computed tomography (PET/CT) identified a remnant of a prosthetic vascular graft sewn to the proximal third of the right axillary artery, through which a catheter-based micro-axial left ventricular assist device was implanted previously as bridge to transplant therapy. The patient presented a rapid clinical improvement with complete functional recovery following the surgical treatment and the antifungal therapy and finally underwent surgical removal of the residual vascular graft. This is the first reported episode of long bone osteomyelitis due to A. granulosus that occurred in a heart transplant recipient without pulmonary infection and was successfully treated with isavuconazole. The PET/CT was useful in supporting the diagnostic process and follow-up. Cryptic fungal species can cause invasive infections, particularly in immunocompromised patients. Molecular methods are crucial in fungal identification.

Current research on fungi in chronic wounds

The occurrence of chronic wounds is a major global health issue. These wounds are difficult to heal as a result of disordered healing mechanisms. The most common types of chronic wounds are diabetic ulcers, pressure ulcers, arterial/venous ulcers and nonhealing surgical wounds. Although bacteria are an important cause of chronic nonhealing wounds, fungi also play a substantial role in them. The fungal infection rate varies with different chronic wound types, but overall, the prevalence of fungi is extremely underestimated in the clinical treatment and management of chronic wounds. Wounds and ulcers can be colonized by host cutaneous, commensal or environmental fungi and evolve into local infections, causing fungemia as well as invasive fungal disease. Furthermore, the fungi involved in nonhealing wound-related infections help commensal bacteria resist antibiotics and the host immune response, forcing wounds to become reservoirs for multiresistant species, which are considered a potential key factor in the microbial bioburden of wounds and ulcers. Fungi can be recalcitrant to the healing process. Biofilm establishment is the predominant mechanism of fungal resistance or tolerance to antimicrobials in chronic nonhealing wounds. Candida albicans yeast and Trichophyton rubrum filamentous fungi are the main fungi involved in chronic wound infection. Fungal species diversity and drug resistance phenotypes in different chronic nonhealing wound types will be emphasized. In this review, we outline the latest research on fungi in chronic wounds and discuss challenges and future perspectives related to diagnosing and managing chronic wounds.

Osteoarticular Mycoses

Osteoarticular mycoses are chronic debilitating infections that require extended courses of antifungal therapy and may warrant expert surgical intervention. As there has been no comprehensive review of these diseases, the International Consortium for Osteoarticular Mycoses prepared a definitive treatise for this important class of infections. Among the etiologies of osteoarticular mycoses are Candida spp., Aspergillus spp., Mucorales, dematiaceous fungi, non-Aspergillus hyaline molds, and endemic mycoses, including those caused by Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species. This review analyzes the history, epidemiology, pathogenesis, clinical manifestations, diagnostic approaches, inflammatory biomarkers, diagnostic imaging modalities, treatments, and outcomes of osteomyelitis and septic arthritis caused by these organisms. Candida osteomyelitis and Candida arthritis are associated with greater events of hematogenous dissemination than those of most other osteoarticular mycoses. Traumatic inoculation is more commonly associated with osteoarticular mycoses caused by Aspergillus and non-Aspergillus molds. Synovial fluid cultures are highly sensitive in the detection of Candida and Aspergillus arthritis. Relapsed infection, particularly in Candida arthritis, may develop in relation to an inadequate duration of therapy. Overall mortality reflects survival from disseminated infection and underlying host factors.

Isavuconazole in the Treatment of Aspergillus fumigatus Fracture-Related Infection: Case Report and Literature Review

Aspergillus fracture-related infection (FRI) is a rare, but severe complication in trauma surgery. The optimal antifungal treatment for Aspergillus osteomyelitis, including FRI, has not been established yet, as only cases have been documented and data on bone penetration of antifungal drugs are scarce. We describe a patient with Aspergillus fumigatus FRI of the tibia who was treated with isavuconazole after developing liver function disturbances during voriconazole therapy. Isavuconazole, the active moiety formed after hydrolysis of the prodrug isavuconazonium sulfate by plasma esterases, was administered in a maintenance dose of 200 mg q24 h, followed by 150 mg q24 h. The patient completed a six-month antifungal treatment course. Although fracture union was not achieved during six months of follow-up after therapy cessation, no confirmatory signs of FRI were observed. Additionally, two literature searches were conducted to review available data on antifungal treatment of Aspergillus osteomyelitis and bone penetration of antifungals. One hundred and eight cases of Aspergillus osteomyelitis, including six (5.6%) FRI cases, were identified. Voriconazole and (lipid formulations of) amphotericin B were the most commonly used antifungals. In three (2.8%) cases isavuconazole was prescribed as salvage therapy. Data on antifungal bone penetration were reported for itraconazole, voriconazole, amphotericin B, anidulafungin and 5-fluorocytosin. Isavuconazole might be a promising alternative for the treatment of Aspergillus osteomyelitis. However, standardized case documentation is needed to evaluate the efficacy of isavuconazole and other antifungals in the treatment of Aspergillus osteomyelitis, including FRI.

Aspergillus spondylitis: case series and literature review

BACKGROUND

Spinal fungal infections, especially spinal Aspergillus infections, are rare in the clinic. Here, we introduce the clinical features, diagnosis, treatment, and prognoses of 6 cases of Aspergillus spondylitis.

METHODS

We retrospectively analysed the complete clinical data of patients with Aspergillus spondylitis treated in our hospital from January 2013 to January 2020.

RESULTS

Aspergillus fumigatus was isolated in 4 cases, and Aspergillus spp. and Aspergillus niger were isolated in 1 case each. All six patients reported varying degrees of focal spinal pain; one patient reported radiating pain, one patient experienced bowel dysfunction and numbness in both lower limbs, and three patients had fever symptoms. One case involved the thoracic spine, one case involved the thoracolumbar junction, and 4 cases involved the lumbar spine. Three patients were already in an immunosuppressed state, and three patients entered an immunosuppressed state after spinal surgery. All six patients were successfully cured, and five required surgery. Of the 5 patients who underwent surgical treatment, 2 had spinal cord compression symptoms, and 3 had spinal instability. At the end of follow-up, 1 patient reported left back pain and 1 patient reported left limb numbness.

CONCLUSION

The clinical manifestations of Aspergillus spondylitis are non-specific, and the diagnosis depends on typical imaging findings and microbiological and histopathological examination results. When there is no spinal instability, spinal nerve compression symptoms, or progressive deterioration, antifungal therapy alone may be considered. If spinal instability, spinal nerve compression, or epidural abscess formation is present, surgery combined with antifungal therapy is recommended.

Diagnosis and management of lumbar Aspergillus spp. discospondylitis using intraoperative cytology and external stabilization in a dog with disseminated infection

Background:

Discospondylitis is an infection of the intervertebral disc and adjacent vertebral endplates. The infectious agent is most commonly a bacterial organism and fungal causes are uncommon.

Case Description:

A 1.5-year-old female entire pug was referred with a 6-week history of right head tilt and progressive non-ambulatory paraparesis. On neurological examination, right facial paralysis and mid and caudal lumbar pain were also detected. Magnetic resonance imaging and computed tomography of the head and spine were performed 3 weeks apart. Findings were consistent with osteolysis of the petrous temporal bone and L2-L3 and L5-L6 vertebral subluxation caused by discospondylitis and osteomyelitis. Disseminated aspergillosis was diagnosed following biopsy and stabilization using an external skeletal spinal fixator. Voriconazol was administered as a medical treatment after surgery. The dog died 3 months later without failure of the construct.

Conclusion:

To the authors’ knowledge, this is the first report using an external fixator for fungal lumbar discospondylitis. The use of an external skeletal spinal fixator should be considered when choosing the surgical technique.

Chronic fungal osteomyelitis of the tibia due to Acremonium curvulum: a rare case

Fungal osteomyelitis is a rare disease which usually presents in an indolent manner. Opportunistic infections due to other non-aspergillus moulds are an emerging entity. We report a case of fungal osteomyelitis due to Acremonium spp in an immunocompetent adult which showed a chronic, indolent course but responded well to treatment with voriconazole. This case highlights the importance of diagnosing the causative agent in fungal osteomyelitis as species specific susceptibility can aid in the treatment of fungal osteomyelitis.

Shape-Depended Biological Properties of Ag3PO4 Microparticles: Evaluation of Antimicrobial Properties and Cytotoxicity in In Vitro Model-Safety Assessment of Potential Clinical Usage

Implant-related infections are an emerging clinical and economic problem. Therefore, we decided to assess potential clinical usefulness and safety of silver orthophosphate microparticles (SOMPs) regarding their shape. We synthesized and then assessed antimicrobial properties and potential cytotoxicity of six shapes of SOMPs (tetrapod, cubes, spheres, tetrahedrons, branched, and rhombic dodecahedron). We found that SOMPs had a high antimicrobial effect; they were more efficient against fungi than bacteria. SOMPs exerted an antimicrobial effect in concentrations not toxic to mammalian cells: human fetal osteoblast (hFOB1.19), osteosarcoma (Saos-2), mouse preosteoblasts (MC3T3-E1), skin fibroblast (HDF), and mouse myoblast (C2C12). At higher concentration SOMPs, induced shape- and concentration-dependent cytotoxicity (according to MTT and BrdU assays). Tetrapod SOMPs had the smallest effect, whereas cubical SOMPs, the highest on cell viability. hFOB1.19 were the most resistant cells and C2C12, the most susceptible ones. We have proven that the induction of oxidative stress and inflammation is involved in the cytotoxic mechanism of SOMPs. After treatment with microparticles, we observed changes in levels of reactive oxygen species, first-line defense antioxidants-superoxide dismutase (SOD1, SOD3), and glutathione peroxidase (GPX4), metalloproteinase (MMP1, MMP3), and NF-κB protein. Neither cell cycle distribution nor ultrastructure was altered as determined by flow cytometry and transmission electron microscopy, respectively. In conclusion, silver orthophosphate may be a safe and effective antimicrobial agent on the implant surface. Spherical-shaped SOMPs are the most promising for biomedical application.

[Fungal infections]

BACKGROUND

Invasive aspergillosis, mucormycosis, and cryptococcosis are severe opportunistic infections in patients with long phases of neutropenia and also after allogeneic stem cell and organ transplantation. Due to the late appearance of clinical signs and the often poor outcome, these diseases require special attention and proactive interventions.

MATERIAL AND METHODS

Published guidelines and selected current literature were reviewed for this article.

RESULTS

Invasive aspergillosis and mucormycosis are typically observed in the upper and lower airways of severely immunocompromized patients. When invasive fungal diseases are suspected, sectional imaging and, if possible, serological testing should be performed as soon as possible. If imaging or serological tests confirm the suspected diagnosis, pre-emptive antimycotic treatment should be started and further confirmation of the diagnosis sought via microbiological and/or histological investigations. Treatment depends on comedication, comorbidity and risk factors, primarily with voriconazole, isavuconazole and liposomal amphotericin B. With the advent of antiretroviral treatment, a decrease of cryptococcosis cases in people with human immunodeficiency virus was observed; however, increasing cases have been reported in patients with new forms of immunosuppression. Cryptococcus spp. predominantly cause central nervous system infections but also pneumonia and bloodstream infections. Diagnostics include blood and cerebrospinal fluid cultures and antigen tests. First line treatment consists of a combination therapy with amphotericin B and flucytosine.

CONCLUSION

An interdisciplinary approach with microbiologists, infectious diseases specialists and radiologists is needed for diagnostics and treatment of invasive fungal diseases.

Invasive Aspergillosis by Aspergillus flavus: Epidemiology, Diagnosis, Antifungal Resistance, and Management

Aspergillus flavus is the second most common etiological agent of invasive aspergillosis (IA) after A. fumigatus. However, most literature describes IA in relation to A. fumigatus or together with other Aspergillus species. Certain differences exist in IA caused by A. flavus and A. fumigatus and studies on A. flavus infections are increasing. Hence, we performed a comprehensive updated review on IA due to A. flavus. A. flavus is the cause of a broad spectrum of human diseases predominantly in Asia, the Middle East, and Africa possibly due to its ability to survive better in hot and arid climatic conditions compared to other Aspergillus spp. Worldwide, ~10% of cases of bronchopulmonary aspergillosis are caused by A. flavus. Outbreaks have usually been associated with construction activities as invasive pulmonary aspergillosis in immunocompromised patients and cutaneous, subcutaneous, and mucosal forms in immunocompetent individuals. Multilocus microsatellite typing is well standardized to differentiate A. flavus isolates into different clades. A. flavus is intrinsically resistant to polyenes. In contrast to A. fumigatus, triazole resistance infrequently occurs in A. flavus and is associated with mutations in the cyp51C gene. Overexpression of efflux pumps in non-wildtype strains lacking mutations in the cyp51 gene can also lead to high voriconazole minimum inhibitory concentrations. Voriconazole remains the drug of choice for treatment, and amphotericin B should be avoided. Primary therapy with echinocandins is not the first choice but the combination with voriconazole or as monotherapy may be used when the azoles and amphotericin B are contraindicated.

The pathogenicity ofAspergillus fumigatus, drug resistance, and nanoparticle delivery

The genus Aspergillus includes fungal species that cause major health issues of significant economic importance. These microorganisms are also the culprit for production of carcinogenic aflatoxins in grain storages, contaminating crops, and economically straining the production process. Aspergillus fumigatus is a very important pathogenic species, being responsible for high human morbidity and mortality on a global basis. The prevalence of these infections in immunosuppressed individuals is on the rise, and physicians struggle with the diagnosis of these deadly pathogens. Several virulence determinants facilitate fungal invasion and evasion of the host immune response. Metabolic functions are also important for virulence and drug resistance, since they allow fungi to obtain nutrients for their own survival and growth. Following a positive diagnostic identification, mortality rates remain high due, in part, to emerging resistance to frequently used antifungal drugs. In this review, we discuss the role of the main virulence, drug target, and drug resistance determinants. We conclude with the review of new technologies being developed to treat aspergillosis. In particular, microsphere and nanoparticle delivery systems are discussed in the context of improving drug bioavailability. Aspergillus will likely continue to cause problematic infections in immunocompromised patients, so it is imperative to improve treatment options.

Aspergillus Osteomyelitis of the Ribs in Immunocompetent Hosts: Report of Two Rare Cases

Introduction

Osteomyelitis is rarely caused by fungi, most common among them being Candida. Aspergillus is a rare cause of fungal osteomyelitis mimics tuberculous osteomyelitis. Aspergillus osteomyelitis (AO) of the ribs is relatively uncommon, with an incidence rate of only 9% among all reported cases of AO. With mortality rates of almost 25%, AO is on the rise attributed to increasing numbers of immunocompromised individuals. There are very few case reports of AO of ribs in immunocompetent individuals. We report two such cases.

Case Report

Case 1: A 51-year-old male developed spontaneous chest pain along right costal margin with a low-grade fever. High-resolution computed tomography chest revealed osteomyelitis of anterolateral chest wall. He did not improve with empirical antitubercular therapy, and subsequent debridement showed polymicrobial pyogenic infection which was managed with appropriate antibiotics elsewhere. Samples were not sent for fungal culture. He presented to us 3 months later, and surgical debridement showed growth of Aspergillus flavus which was managed with oral voriconazole. The lesion healed with no recurrence at 24-month follow-up. Case 2: A 40-year-old male presented to our institute with left-sided chest pain, low-grade fever, and loss of appetite. There was a history of injury with a sharp piece of wood 2 years earlier. Magnetic resonance imaging defined the lesion which was biopsied under ultrasound guidance. Cultures grew A. flavus which was treated with oral voriconazole. He had complete clinical improvement at 16-month follow-up.

Conclusion

More number of AO cases are being reported in immunocompetent individuals. Variability in clinical picture, rarity, misdiagnosis, empirical therapy, and failure to send deep tissue samples for fungal cultures are some of the reasons for the high mortality rates. It is paramount in today's scenario of atypical presentations, to obtain deep tissue for all cultures including fungal culture and histopathology, either surgically or under image guidance to achieve good clinical outcomes. Our study highlights that following the strict protocol of obtaining tissue for fungal culture, systemic antifungal therapy, and surgical debridement where necessary can help to diagnose and treat this rare pathology and ensure the good clinical outcome.

Bone and joint infections caused by mucormycetes: A challenging osteoarticular mycosis of the twenty-first century

Osteomyelitis and arthritis caused by mucormycetes are rare diseases that rank among the most challenging complications in orthopedic and trauma surgery. The aim of this work is to review the epidemiological, clinical, diagnostic, and therapeutic aspects of the osteoarticular mucormycosis with particular emphasis on high-risk patients. A systematic review of osteoarticular mucormycosis was performed using PUBMED and EMBASE databases from 1978 to 2014. Among 34 patients with median age 41 (0.5-73 years), 24 (71%) were males. While 12 (35%) were immunocompromised patients, 14 (41%) had prior surgery, and seven (21%) suffered trauma. Other underlying conditions included diabetes mellitus, hematological malignancies, transplantation, and corticosteroid therapy. The median diagnostic delay from onset of symptoms and signs was 60 (10-180) days. The principal mechanism of the infection was direct inoculation (n = 19; 56%), and in immunocompromised patients was usually hematogenous disseminated. The long bones were infected by trauma or surgery, while a wide variety of bones were involved by hematogenous dissemination. Combined surgery and amphotericin B treatment were implemented in 28 (82%) and eight (23%) had an unfavorable outcome. Osteoarticular mucormycosis occurs most frequently after trauma or surgical procedures. These infections are progressively destructive and more virulent in individuals with impaired immune systems. Early diagnosis, timely administration of amphotericin B, control of underlying conditions, and surgical debridement of infected tissue are critical for successful management of osteoarticular mucormycosis.

Aspergillus Vertebral Osteomyelitis Complicating Pulmonary Granuloma in an Immunocompetent Adult

OBJECTIVE

The aim of this report is to describe a case with Aspergillus vertebral osteomyelitis complicating pulmonary granuloma in an immunocompetent adult.

CLINICAL PRESENTATION AND INTERVENTION

A 53-year-old male patient was found to have lesions on lumbar vertebra 5 months after thoracoscopic resection of pulmonary granuloma that lacked a definite etiology. Three operations on the lumbar lesions were performed successively; however, an Aspergillus infection was not confirmed until hyphae were clearly detected at the last surgery. The patient was treated with voriconazole and recovered well.

CONCLUSION

This case shows that simultaneous occurrence of granulomatous nodules in the lung and vertebral lesions should raise suspicion of aspergillosis, even in immunocompetent patients.

Rare Case of Aspergillus ochraceus Osteomyelitis of Calcaneus Bone in a Patient with Diabetic Foot Ulcers

Diabetes is the most common metabolic disease in humans. One of the major complications of the disease is foot ulcer that is prone to infection. The most common causes of infection which have been reported in these patients are bacteria and fungi such as Candida, Aspergillus, and Rhizopus species. We report one such rare case with calcaneal osteomyelitis caused by Aspergillus ochraceus in a patient with diabetic foot osteomyelitis. The case was a 68-year-old male with a history of type II diabetes for 2 years. The patient had two ulcers on the right heel bones for the past 6 months with no significant improvement. One of the most important predisposing factors to infectious diseases, especially opportunistic fungal infection, is diabetes mellitus. Aspergillus species can involve bony tissue through vascular system, direct infection, and trauma. Proper and early diagnosis and treatment of diabetic foot infection can reduce or prevent complications, such as osteomyelitis and amputation. The annual examination of feet for skin and nail lesion, sensation, anatomical changes, and vascular circulation can be useful for prevention and control of infection.

Th17 cytokine deficiency in patients with Aspergillus skull base osteomyelitis

BACKGROUND

Fungal skull base osteomyelitis (SBO) is a severe complication of otitis externa or sinonasal infection, and is mainly caused by Aspergillus species. Here we investigate innate and adaptive immune responses in patients with Aspergillus SBO to identify defects in the immune response that could explain the susceptibility to this devastating disease.

METHODS

Peripheral blood mononuclear cells isolated from six patients with Aspergillus SBO and healthy volunteers were stimulated with various microbial stimuli, among which also the fungal pathogens Candida albicans and Aspergillus fumigatus. The proinflammatory cytokines IL-6, TNFα and IL-1β, and the T-helper cell-derived cytokines IFNγ, IL-17 and IL-22 were measured in cell culture supernatants by ELISA.

RESULTS

Proinflammatory cytokine responses did not differ between SBO patients and healthy volunteers. The Candida- and Aspergillus-specific Th17 response (production of IL-17 and IL-22) was significantly decreased in the SBO patients compared to healthy individuals, while Th1 cytokine response (IFNγ production) did not differ between the two groups.

CONCLUSIONS

We show that patients with Aspergillus skull base osteomyelitis infection have specific defects in Th17 responses. Since IL-17 and IL-22 are important for stimulating antifungal host defense, we hypothesize that strategies that have the ability to improve IL-17 and IL-22 production may be useful as adjuvant immunotherapy in patients with Aspergillus SBO.