El tratamiento de la mucormicosis (cigomicosis) en el siglo xxi

Infections due to zygomycetes, caused by mucorales and entomophthorales, are characterized by angioinvasion and invasion of neighboring organs or structures. Mucorales most commonly cause rhinocerebral, pulmonary, cutaneous or disseminated infection and its spread is favored by several diseases (such as diabetes or chronic kidney disease) and risk factors (neutropenia, immunosuppression, iron overload). They have a high mortality rate, and the key to success in their treatment are early diagnosis, prompt administration of antifungal treatment, and extensive surgical debridement. Currently, isavuconazole constitutes an option for the treatment of those mucormycosis refractory to liposomal amphotericin B. Due to its pharmacokinetic and pharmacodynamic characteristics and its low toxicity, it is also the best choice for maintenance therapy.     

中国大陆肺接合菌病102例回顾性分析

目的 总结与探讨中国大陆地区近25 a肺接合菌病的流行病学特点及诊疗情况.方法 检索分析重庆维普、CNKI系列数据库、万方数据库、中国医师协会全文期刊库及Pubmed等数据库中1988年以来的中国大陆地区肺接合菌病的相关文献资料.结果 共检索文献73篇,病例102例.患者的平均发病年龄为48.4岁,男女比例为2.46∶1,总死亡率为40.82％.我国肺接合菌病多见于糖尿病、HIV感染、病毒性肝炎、长期使用糖皮质激素和（或）免疫抑制剂等伴基础疾病的人群.其临床及影像学检查无特异性,诊断主要依赖于真菌学及组织病理学检查.治疗方法首选两性霉素B,联合手术治疗较之单独抗真菌药物疗效更好.结论 近年来中国大陆地区肺接合菌病发病率呈上升趋势.对高度怀疑肺接合菌感染的患者,宜尽早启动抗真菌治疗,及时联合病灶切除者疗效更佳.     

Post-Covid alliance-mucormycosis,a fatal sequel to the pandemic in India

As the battle against the deadly Covid-19 pandemic is still continuing worldwide, several complications are being reported in patients who have recovered post-covid. One such lethal complication being reported in patients in India in recent times, who have tested positive for Covid-19 and are gradually recovering, is a fungal disease called Mucormycosis or the black fungus. With several hundreds of cases being reported all over the country, it has triggered an additional wave of panic among the general public. Post-Covid-19 patients who are more vulnerable to Mucormycosis are those with a history of poorly controlled diabetes mellitus and also those who are immuno-compromised and have been treated with steroids and other drugs for Covid-19. The aim of this short review is to briefly cover the epidemiology of mucormycosis, its possible pathophysiology in Post Covid scenario, the clinical presentation and its diagnosis and management.     

Molecular docking of glucosamine-6-phosphate synthase in Rhizopus oryzae

Recent expansion of immunocompromised population has led to significant rise in zygomycosis caused by filamentous fungus Rhizopus oryzae. Due to emergence of fungal resistance and side-effects of antifungal drugs, there is increased demand for novel drug targets. The current study elucidates molecular interactions of peptide drugs with G-6-P synthase (catalyzing the rate-limiting step of fungal cell wall biosynthetic pathway) of R.oryzae by molecular docking studies. The PDB structures of enzyme in R.oryzae are not known which were predicted using I-TASSER server and validated with PROCHECK. Peptide inhibitors, FMDP and ADGP previously used against enzyme of E.coli (PDBid: 1XFF), were used for docking studies of enzyme in R.oryzae by SchrödingerMaestro v9.1. To investigate binding between enzyme and inhibitors, Glide and Induced Fit docking were performed. IFD results of 1XFF with FMDP yielded C1, R73, W74, T76, G99 and D123 as the binding sites. C379 and Q427 appear to be vital for binding of R.oryzae enzymes to inhibitors. The comparison results of IFD scores of enzyme in R.oryzae and E.coli (PDBid: 2BPL) yield appreciable score, hinting at the probable effectiveness of inhibitors FMDP and ADGP against R.oryzae, with ADGP showing an improved enzyme affinity. Moreover, the two copies of gene G-6-P synthase due to extensive fungal gene duplication, in R. oryzae eliminating the problem of drug ineffectiveness could act as a potential antifungal drug target in R. oryzae with the application of peptide ligands.     

Gastrointestinal zygomycosis: a report of three cases

Three cases of gastrointestinal zygomycosis, probably caused by Basidiobolus ranarum, are described. The diagnosis was based on morphology of the fungal elements in infected tissues and histopathologic findings. All the three patients responded favorably to management strategy that included surgical resection of the infected portion of the bowel and institution of specific antifungal therapy.     

Ovine ruminal and abomasal zygomycosis

Thirty of four hundred lambs developed diarrhoea subsequent to broad-spectrum antibiotic therapy initiated because of apathy and weight loss after start of fattening. At necropsy mycotic rumenitis and abomasitis was diagnosed in one lamb. Especially intense an antibiotic therapy seems to have contributed to the fungal infection.

The aetiological diagnosis was accomplished by indirect immunofluorescence staining of fungi in tissue sections. A strong and uniform reaction was obtained with heterologously absorbed anti-Absidia corymbifera hyperimmune rabbit antiserum, whereas no reactivity was seen when heterologously absorbed hyperimmune rabbit antisera towards Aspergillus spp. and Candida spp. were applied. Thus, the infective agent was identified as a zygomycete, probably Absidia corymbifera, also a common cause of mycosis in the stomachs of cattle treated intensively with antibiotics.