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Aykur M, Dagci H. Molecular identification of Acanthamoeba spp., Balamuthia mandrillaris and Naegleria fowleri in soil samples using quantitative real-time PCR assay in Turkey; Hidden danger in the soil! Acta Trop 2023:106956. [PMID: 37244403 DOI: 10.1016/j.actatropica.2023.106956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 05/29/2023]
Abstract
Acanthamoeba spp., Balamuthia mandrillaris, and Naegleria fowleri are pathogenic free-living amoeba (FLA) and are commonly found in the environment, particularly soil. This pathogenic FLA causes central nervous system-affecting granulomatous amebic encephalitis (GAE) or primary amebic meningoencephalitis (PAM) and can also cause keratitis and skin infections. In the present study, we aimed to determine the quantitative concentration of Acanthamoeba spp., B. mandrillaris, and N. fowleri in soil samples collected from places where human contact is high by using a qPCR assay in Izmir, Turkey. A total of 45.71% (n=16) of Acanthamoeba spp., 20% (n=7) of B. mandrillaris, and 17.4% (n=6) of N. fowleri were detected in five different soil sources by the qPCR assay. The quantitative concentration of Acanthamoeba spp., B. mandrillaris, and N. fowleri in various soil sources was calculated at 10 × 105 - 6 × 102, 47 × 104 to 39 × 103, and 9 × 103 - 8 × 102 plasmid copies/gr, respectively. While the highest quantitative concentration of Acanthamoeba spp. and B. mandrillaris was determined in garden soil samples, N. fowleri was detected in potting soil samples. Three different genotypes T2 (18.75%), T4 (56.25%), and T5 (25%) were identified from Acanthamoeba-positive soil samples. Acanthamoeba T4 genotype was the most frequently detected genotype from soil samples and is also the most common genotype to cause infection in humans and animals. To the best of our knowledge, the present study is the first study to identify genotype T5 in soil samples from Turkey. In conclusion, people and especially children should be aware of the hidden danger in the garden and potting soil samples that come into contact most frequently. Public health awareness should be raised about human infections that may be encountered due to contact with the soil. Public health specialists should raise awareness about this hidden danger in soil.
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Affiliation(s)
- Mehmet Aykur
- Department of Parasitology, Tokat Gaziosmanpasa University Medical School, Tokat, Turkey; Department of Parasitology, Ege University Medical School, İzmir, Turkey.
| | - Hande Dagci
- Department of Parasitology, Ege University Medical School, İzmir, Turkey
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Liu J, Zhang W, Wu S, Zeng T, Luo F, Jiang Q, Yang R. A clinical case report of Balamuthia granulomatous amoebic encephalitis in a non-immunocompromised patient and literature review. BMC Infect Dis 2023; 23:245. [PMID: 37072710 PMCID: PMC10114318 DOI: 10.1186/s12879-023-08228-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 04/05/2023] [Indexed: 04/20/2023] Open
Abstract
BACKGROUND Balamuthia granulomatous amoebic encephalitis (GAE) is a peculiar parasitic infectious disease of the central nervous system, about 39% of the infected Balamuthia GAE patients were found to be immunocompromised and is extremely rare clinically. The presence of trophozoites in diseased tissue is an important basis for pathological diagnosis of GAE. Balamuthia GAE is a rare and highly fatal infection for which there is no effective treatment plan in clinical practice. CASE PRESENTATION This paper reports clinical data from a patient with Balamuthia GAE to improve physician understanding of the disease and diagnostic accuracy of imaging and reduce misdiagnosis. A 61-year-old male poultry farmer presented with moderate swelling pain in the right frontoparietal region without obvious inducement three weeks ago. Head computed tomography(CT) and magnetic resonance imaging(MRI) revealed a space-occupying lesion in the right frontal lobe. Intially clinical imaging diagnosed it as a high-grade astrocytoma. The pathological diagnosis of the lesion was inflammatory granulomatous lesions with extensive necrosis, suggesting amoeba infection. The pathogen detected by metagenomic next-generation sequencing (mNGS) is Balamuthia mandrillaris, the final pathological diagnosis was Balamuthia GAE. CONCLUSION When a head MRI shows irregular or annular enhancement, clinicians should not blindly diagnose common diseases such as brain tumors. Although Balamuthia GAE accounts for only a small proportion of intracranial infections, it should be considered in the differential diagnosis.
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Affiliation(s)
- Jun Liu
- Department of Neurosurgery, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China
| | - Wenjun Zhang
- Department of Rehabilitation Medicine, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China
| | - Shanlian Wu
- Department of Pathology, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China
| | - Tianxiang Zeng
- Department of Neurosurgery, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China
| | - Fei Luo
- Department of Neurosurgery, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China
| | - Qiuhua Jiang
- Department of Neurosurgery, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China
| | - Ruijin Yang
- Department of Neurosurgery, Ganzhou People's Hospital, Ganzhou, 341000, Jiangxi Province, People's Republic of China.
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Chen XT, Zhang Q, Wen SY, Chen FF, Zhou CQ. Pathogenic free-living amoebic encephalitis from 48 cases in China: A systematic review. Front Neurol 2023; 14:1100785. [PMID: 36846140 PMCID: PMC9947844 DOI: 10.3389/fneur.2023.1100785] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/26/2023] [Indexed: 02/11/2023] Open
Abstract
Background Free-living amoebae (FLA) including Naegleria fowleri, Acanthamoeba spp., and Balamuthia mandrillaris can become pathogenic and cause severe cerebral infections, named primary amoebic meningoencephalitis (PAM), granulomatous amoebic encephalitis (GAE), and balamuthia amoebic encephalitis (BAE), respectively. FLA encephalitis has been reported across China, but the clinical data descriptions and analytical results of these different reports vary widely. Currently, no consensus treatment has been established. We conduct a systematic review to evaluate the exposure location, clinical symptoms, diagnosis, treatment, and prognosis of three FLA encephalitis and aim to reveal the differences between three FLA encephalitis in China. Methods We used MEDLINE (PubMed interface), EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang database, and China Biology Medicine disc (CBMdisc) databases for literatures published and manually retrieve the hospital records of our hospital. The search time was up to August 30, 2022, with no language restrictions. Results After excluding possible duplicate cases, a total of 48 patients of three FLA encephalitis were collected. One from the medical records of our hospital and 47 patients from 31 different studies. There were 11 patients of PAM, 10 patients of GAE, and 27 patients of BAE. The onset of PAM is mostly acute or subacute, and the clinical symptoms are acute and fulminant hemorrhagic meningoencephalitis. Most patients with GAE and BAE have an insidious onset and a chronic course. A total of 21 BAE patients (77.8%) had skin lesions before onset of symptoms. Additionally, 37 cases (77.1%) were diagnosed with FLA encephalitis before death. And there were 4 of PAM, 2 of GAE, and 10 of BAE diagnosed using next generation sequencing. No single agent can be proposed as the ideal therapy by itself. Only 6 cases were successfully treated. Conclusions This review provides an overview of the available data and studies of FLA encephalitis in China and identify some potential differences. FLA encephalitis is a rare but pathogenic infection, and physicians should early identify this encephalitis to improve survival.
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Affiliation(s)
| | | | | | | | - Chang-Qing Zhou
- Department of Neurology, Bishan Hospital of Chongqing Medical University, Chongqing, China
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4
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Fan X, Chen T, Yang H, Gao Y, Chen Y. Encephalomyelomeningitis Caused by Balamuthia mandrillaris: A Case Report and Literature Review. Infect Drug Resist 2023; 16:727-733. [PMID: 36756612 PMCID: PMC9901442 DOI: 10.2147/idr.s400692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 01/21/2023] [Indexed: 02/05/2023] Open
Abstract
Central nervous system infection by Balamuthia mandrillaris is a rare and severe condition, which has a fatality rate of approximately 95% and often evades timely diagnosis due to its rarity and non-specific clinical manifestations. Here, we report a case of encephalomyelomeningitis caused by B. mandrillaris in a male who presented with transient coma, nausea, and vomiting when working in a garbage dump. Initial magnetic resonance imaging (MRI) of the brain showed normal signals. Despite receiving steroids as well as antibacterial and antiviral treatment, he developed urinary and fecal dysfunction, inability to walk, and deterioration of consciousness. Both brain and spinal cord MRI revealed abnormal findings, and next-generation sequencing of the cerebrospinal fluid showed the presence of B. mandrillaris. A combination of fluconazole and albendazole was administered; however, the patient deteriorated gradually and died 30 days after the onset. We suggest the unbiased metagenomic sequencing of the affected tissues/CSF in patients with CNS infections that are difficult to diagnose or treat, and multiple tests at different stages of the disease may be required.
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Affiliation(s)
- XueMei Fan
- Department of Neurology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - TianWen Chen
- Department of Neurology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Hui Yang
- Department of Neurology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China
| | - Yue Gao
- Department of General Practice, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China,Yue Gao, Tel +86 13706511908; +86 531-56006851, Email
| | - Yan Chen
- Department of Neurology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China,Correspondence: Yan Chen, Department of Neurology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, No. 261, Huan Sha Road, Shangcheng District, Hangzhou, People’s Republic of China, Tel +86 15397086693; +86 531-56006952, Email
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Tao K, Wang T, Zhang L, Yang XC, Zhai ZF. Fatal Balamuthia mandrillaris infection with red plaques on the nasal dorsum as the first presentation. An Bras Dermatol 2022; 97:498-500. [PMID: 35691739 PMCID: PMC9263639 DOI: 10.1016/j.abd.2021.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 11/29/2021] [Accepted: 12/01/2021] [Indexed: 11/02/2022] Open
Abstract
Balamuthia mandrillaris infection is a rare infectious disease around the world, with high rates of morbidity and mortality. Its early and correct diagnosis is a big challenge for us, and without it the delay in starting effective treatment can lead to the development of encephalitis. This is a report of a case of Balamuthia mandrillaris infection in a Chinese boy, with red plaques on the nasal dorsum as the first presentation, who finally developed into fatal encephalitis. The authors have reviewed the related literature and share the special skin features in order to favor the early diagnosis of the disease and increase the chances of survival.
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Affiliation(s)
- Kang Tao
- Department of Dermatology and Venereology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Ting Wang
- Department of Dermatology and Venereology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Lian Zhang
- Department of Dermatology and Venereology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Xi-Chuan Yang
- Department of Dermatology and Venereology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Zhi-Fang Zhai
- Department of Dermatology and Venereology, Southwest Hospital, Army Medical University, Chongqing, China.
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Zhang Z, Liang J, Wei R, Feng X, Wang L, Wang L, Zhao P, Yu H, Gu Y, Yao Z. Facial Balamuthia mandrillaris infection with neurological involvement in an immunocompetent child. THE LANCET. INFECTIOUS DISEASES 2022; 22:e93-e100. [PMID: 34838200 DOI: 10.1016/s1473-3099(21)00334-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/14/2021] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
Cutaneous infection by Balamuthia mandrillaris is a rare condition that is sometimes complicated by life-threatening CNS involvement. It often evades timely diagnosis due to its rarity and non-specific clinical manifestations. Patients can be either immunocompetent or immunocompromised. It is probably transmitted via inhalation or inoculation through broken skin, and then spreads to the brain and other organs through haematogenous spread. It is important for clinicians to be aware of this disease because rapid diagnosis and subsequent therapy has, in some cases, been associated with survival. In this Grand Round, we report the case of a 7-year-old boy who presented with large, chronic plaques on his face. Several biopsies showed non-specific granulomatous inflammation. The patient deteriorated rapidly and died within 1 month of displaying abnormal symptoms in the CNS. Immunohistochemical staining of skin tissue identified B mandrillaris as the infectious agent. The diagnosis was confirmed with PCR, which detected B mandrillaris DNA in formalin-fixed skin tissue sections. B mandrillaris infection should be considered in the differential diagnosis of patients with chronic granulomatous lesions. We also reviewed the epidemiology, B mandrillaris in nature and in the laboratory, clinical manifestations, histopathology, diagnosis, and treatment of infection.
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Affiliation(s)
- Zhen Zhang
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jianying Liang
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ruoqu Wei
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiaobo Feng
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Lei Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, China
| | - Liuhui Wang
- Department of Dermatology, Children's Hospital of Fudan University, Shanghai, China
| | - Piaoping Zhao
- Department of Dermatology, Children's Hospital of Fudan University, Shanghai, China
| | - Hong Yu
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yan Gu
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Zhirong Yao
- Department of Dermatology, Xinhua Hospital, and Institute of Dermatology, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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7
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Alvarez P, Torres-Cabala C, Gotuzzo E, Bravo F. Cutaneous balamuthiasis: A clinicopathological study. JAAD Int 2022; 6:51-58. [PMID: 35059659 PMCID: PMC8760460 DOI: 10.1016/j.jdin.2021.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2021] [Indexed: 11/19/2022] Open
Abstract
Introduction Methods Results Conclusion
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Affiliation(s)
- Patricia Alvarez
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Correspondence to: Patricia Alvarez, MD, Patologia cutánea, Av. Angamos Oeste 896, Miraflores Lima, Peru.
| | - Carlos Torres-Cabala
- Departments of Pathology and Dermatology, The University of Texas, MD Anderson Cancer Center, Houston, Texas
| | - Eduardo Gotuzzo
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Enfermedades Infecciosas, Tropicales y Dermatológicas, Hospital Nacional Cayetano Heredia, Lima, Peru
| | - Francisco Bravo
- Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Patología, Hospital Cayetano Heredia, Lima, Peru
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Wang L, Cheng W, Li B, Jian Z, Qi X, Sun D, Gao J, Lu X, Yang Y, Lin K, Lu C, Chen J, Li C, Wang G, Gao T. Balamuthia mandrillaris infection in China: a retrospective report of 28 cases. Emerg Microbes Infect 2021; 9:2348-2357. [PMID: 33048025 PMCID: PMC7599003 DOI: 10.1080/22221751.2020.1835447] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Balamuthia mandrillaris infection is a rare and fatal disease. We have recorded 28 cases of Balamuthia mandrillaris infection during the past 20 years. Eighteen patients (64%) were male and 10 (36%) were female. Patient age ranged from 3 to 74 (mean, 27) years. Patient locations were distributed among 12 Provinces in China. Twenty-seven (96%) patients lived in rural areas, and 17 (61%) patients reported a history of trauma before the appearance of skin lesions. All cases presented with skin lesions as the primary symptom, and 16 (57%) cases developed encephalitis. Histopathology of skin lesions revealed granulomatous changes with histiocytes, lymphocytes, and plasma cells infiltration. Amebas were identified in all cases with immunohistochemical staining. Follow-up information was available in 27 (96%) cases. Fifteen (56%) patients died due to encephalitis and 12 (44%) were free of disease after treatment. Our results show that the clinical characteristics of Balamuthia mandrillaris infection in China are very different from those in the US. Infection of traumatized skin may play an important role in the pathogenesis of the disease in China. Encephalitis usually develops 3–4 years after skin lesions in Chinese cases. Patients with only skin lesions have a higher cure rate than patients with encephalitis.
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Affiliation(s)
- Lei Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Wenjing Cheng
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Bing Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Zhe Jian
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Xianlong Qi
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Dongjie Sun
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Jian Gao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Xuetao Lu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Yi Yang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Kun Lin
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Chuanlong Lu
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Jiaxi Chen
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Chunying Li
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Gang Wang
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
| | - Tianwen Gao
- Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xian, People's Republic of China
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[First case report of the Balamuthia mandrillaris in the Camaná district of Arequipa, Peru]. Rev Argent Microbiol 2020; 53:129-134. [PMID: 33012571 DOI: 10.1016/j.ram.2020.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 04/11/2020] [Accepted: 05/25/2020] [Indexed: 11/21/2022] Open
Abstract
Infections by free-living amoebas cause cutaneous and neurological compromise. These conditions have a low frequency, but a high lethality more than 98%. Generally, the clinical picture is nonspecific; the laboratory tests dońt help, so it represents a diagnostic and therapeutic challenge. In this report, we present the case of a 21-year-old patient, who was hospitalized for a convulsive syndrome with brain tumors, in addition to a cutaneous lesion on the right thigh. Histopathological analysis, PCR and the clinical picture allowed the diagnosis of granulomatous amebic encephalitis. Despite the treatment, the patient had a fatal outcome.
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Functional Assessment of 2,177 U.S. and International Drugs Identifies the Quinoline Nitroxoline as a Potent Amoebicidal Agent against the Pathogen Balamuthia mandrillaris. mBio 2018; 9:mBio.02051-18. [PMID: 30377287 PMCID: PMC6212833 DOI: 10.1128/mbio.02051-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Balamuthia mandrillaris is responsible for hundreds of reported cases of amoebic encephalitis, the majority of which have been fatal. Despite being an exceptionally deadly pathogen, B. mandrillaris is understudied, leaving many open questions regarding epidemiology, diagnosis, and treatment. Due to the lack of effective drugs to fight B. mandrillaris infections, mortality rates remain high even for patients receiving intensive care. This report addresses the need for new treatment options through a drug repurposing screen to identify novel B. mandrillaris inhibitors. The most promising candidate identified was the quinoline antibiotic nitroxoline, which has a long history of safe use in humans. We show that nitroxoline kills B. mandrillaris at pharmacologically relevant concentrations and exhibits greater potency and selectivity than drugs commonly used in the current standard of care. The findings that we present demonstrate the potential of nitroxoline to be an important new tool in the treatment of life-threatening B. mandrillaris infections. Balamuthia mandrillaris is a pathogenic free-living amoeba that causes a rare but almost always fatal infection of the central nervous system called granulomatous amoebic encephalitis (GAE). Two distinct forms of B. mandrillaris—a proliferative trophozoite form and a nonproliferative cyst form, which is highly resistant to harsh physical and chemical conditions—have been isolated from environmental samples worldwide and are both observed in infected tissue. Patients suffering from GAE are typically treated with aggressive and prolonged multidrug regimens that often include the antimicrobial agents miltefosine and pentamidine isethionate. However, survival rates remain low, and studies evaluating the susceptibility of B. mandrillaris to these compounds and other potential therapeutics are limited. To address the need for more-effective treatments, we screened 2,177 clinically approved compounds for in vitro activity against B. mandrillaris. The quinoline antibiotic nitroxoline (8-hydroxy-5-nitroquinoline), which has safely been used in humans to treat urinary tract infections, was identified as a lead compound. We show that nitroxoline inhibits both trophozoites and cysts at low micromolar concentrations, which are within a pharmacologically relevant range. We compared the in vitro efficacy of nitroxoline to that of drugs currently used in the standard of care for GAE and found that nitroxoline is the most potent and selective inhibitor of B. mandrillaris tested. Furthermore, we demonstrate that nitroxoline prevents B. mandrillaris-mediated destruction of host cells in cultured fibroblast and primary brain explant models also at pharmacologically relevant concentrations. Taken together, our findings indicate that nitroxoline is a promising candidate for repurposing as a novel treatment of B. mandrillaris infections.
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Takei K, Toyoshima M, Nakamura M, Sato M, Shimizu H, Inoue C, Shimizu Y, Yagita K. An Acute Case of Granulomatous Amoebic Encephalitis-Balamuthia mandrillaris Infection. Intern Med 2018; 57:1313-1316. [PMID: 29321406 PMCID: PMC5980817 DOI: 10.2169/internalmedicine.0011-17] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 74-year-old woman who exhibited drowsiness was referred to our hospital. Enhanced head magnetic resonance imaging (MRI) revealed multiple ring-enhancing lesions and lesions showing partial mild hemorrhaging. The patient gradually progressed to a comatose condition with notable brain deterioration of unknown cause on follow-up MRI. On day nine, the patient inexplicably died, although brain herniation was suspected. Autopsy and histopathology revealed numerous amoebic trophozoites in the perivascular spaces and within the necrotic tissue. Brain immunostaining tested positive for Balamuthia mandrillaris. Infection due to free-living amoeba is rare in Japan; however, it may increase in the near future due to unknown reasons.
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Affiliation(s)
| | | | | | | | | | - Chihiro Inoue
- Department of Pathology, Tohoku University School of Medicine, Japan
| | - Yoshio Shimizu
- Department of Pathology, Tohoku University School of Medicine, Japan
| | - Kenji Yagita
- Department of Parasitology, National Institute of Infectious Diseases, Japan
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Niyyati M, Karamati SA, Lorenzo Morales J, Lasjerdi Z. Isolation of Balamuthia mandrillaris from soil samples in North-Western Iran. Parasitol Res 2016; 115:541-5. [PMID: 26468147 DOI: 10.1007/s00436-015-4770-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 10/01/2015] [Indexed: 01/11/2023]
Abstract
Balamuthia mandrillaris is an opportunistic free-living amoebae (FLA) which has been reported as the causative agent of the fatal Balamuthia amoebic encephalitis (BAE). Currently, the transmission dynamics of this pathogen remain poorly understood although the organism has been associated with soils, and thus, soil exposure has been identified as a risk factor for this pathogenic amoeba. Nevertheless, environmental isolation of B. mandrillaris is a rare event and strains of this amoebic species have been isolated from soil and dust sources only in seven previous reports (Iran, Mexico, USA, Peru, Costa Rica, Guinea Bissau, and Jamaica). In Iran, a previous study reported the isolation of B. mandrillaris from dust collected in the city of Tehran and free of known infectious involvement. Therefore, in this work, 55 soil samples collected from public and recreational areas of East Azerbaijan, North-Western Iran, were investigated for the presence of this pathogen. Samples were cultured in 2% non-nutrient agar plates and were monitored for the presence of B. mandrillaris-like trophozoites and/or cysts. Those samples that were positive for these amoebae by microscopic criteria were then confirmed by PCR amplification and DNA sequencing of the mitochondrial 16S ribosomal DNA (rDNA) of B. mandrillaris. The obtained results revealed the presence of this emerging pathogen in 5 of 55 samples included in the study. Homology analysis of the obtained DNA sequences revealed high similarity with previously isolated strains from clinical and environmental sources. To the best of our knowledge, this is the first report on the isolation of B. mandrillaris from soil sources in Iran related to human activity and the second time that this pathogen is isolated from the environment in this country.
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