Mucormycosis, New Causative Agents, and New Susceptible Populations: Review of Cases in a Tertiary Care Hospital in Iran (2007-2021)

Background

Mucormycosis is an aggressive opportunistic fungal infection that afflicts patients with severe underlying immunosuppression, uncontrolled hyperglycemia and/or ketoacidosis, iron overload, and occasionally healthy patients who are inoculated with fungal spores through traumatic injuries. The epidemiology of mucormycosis has changed after the COVID-19 pandemic, with mucormycosis becoming the most common and the fatal coinfection.

Methods

In a retrospective, cross-sectional study, 82 hospitalized patients with a definite diagnosis of mucormycosis were reported from 2007 to 2021 in a referral, tertiary care center in Tehran, Iran.

Results

The number of post-COVID cases increased 4.6 times per year, with 41.5% of patients admitted during the two years of the pandemic. Mucormycosis was more common in women (57.3%), and the most common underlying diseases were diabetes (43.7%), both COVID-19 and diabetes (23.2%), cancer (11%), rheumatic diseases (7.3%), COVID-19 without other underlying diseases (6.1%), and transplantation (4.9%). Rhino-orbito-cerebral Mucormycosis (54.9%) followed by Sino-orbital infection (23.2%) was the most common presentation. There was a significant relationship between the use of immunosuppressive agents and the development of Mucormycosis (P<0.005) The average mortality was 41.5%, but this ratio decreased to 35% during the pandemic era.

Conclusion

The COVID-19 pandemic caused a 4.6-fold increase in the number of mucormycosis patients, and there was a significant relationship between hyperglycemia, corticosteroid use, and mucormycosis. The death rate during the COVID-19 pandemic has decreased by 6.5%, and during the COVID period, the interval between the arrival of a patient with mucormycosis and the start of the correct treatment was significantly decreased.

Cerebellopontine angle meningioma originating from choroid plexus of the foramen of Luschka: An extremely rare entity and overlook of literature

INTRODUCTION AND IMPORTANCE

Meningiomas without dural attachments are quite a novelty, with such meningiomas in the posterior fossa being even more far and few between. The authors describe an extremely rare cerebellopontine angle (CPA) meningioma lacking a dural attachment arising from the choroid plexus of the foramen of Luschka (CPFOL).

CASE PRESENTATION

A 35-year-old male presented to our center complaining of a generalized and progressive headache for 10 months. A 3 cm × 4 cm well-defined lesion in the left CPA, hypointense in T1 and hyperintense in T2-weighted magnetic resonance imaging (MRI), was noted with no evident dural base or dural attachment. CPFOL was appreciated right at the point where the tumoral base was detected, which implied that the tumor originated from CPFOL. A gross total resection (GTR) was achieved, with the postoperative period remaining uneventful. The histopathologic investigation confirmed a transitional meningioma World Health Organization (WHO) grade I with no atypical features.

CLINICAL DISCUSSION

Meningioma without dural attachment remains a rare phenomenon, with few available in English literature, and such pathology in the posterior fossa is even more unusual. Discriminating between CPFOL and another kind of CPA meningioma is mandatory when dealing with intracranial meningioma surgeries.

CONCLUSION

While managing a space-occupying lesion around CPA, although extremely rare, a meningioma originating from CPFOL is suggested to be included in the differentials with necessary imaging analysis and advised to be imperatively pursued before proceeding for surgical intervention.

A rare case of iatrogenic intracranial hypotension due to a minor CSF leakage

Intracranial hypotension (IH) represents a rare complication, mainly following cerebrospinal fluid (CSF) leakage at the thoracic or cervicothoracic junction level. Iatrogenic IH may be expected secondary to the previous surgery or other procedures invading the patient's dura. Magnetic resonance imaging (MRI), computerized tomography (CT) scan images, CT cisternography, and magnetic resonance cerebrospinal fluid flow (MR CSF) remains the modality of choice to establish the diagnosis. The patient is in her late sixth decade, reflecting a history of progressive headaches, nausea, and vomiting. Once a diagnosis of foramen magnum meningioma was established using MRI, total microscopic resection was applied. Brain sagging and subdural fluid collection were identified on postoperative day three, suggesting intracranial hypotension due to cerebrospinal fluid leakage. Diagnosing IH following the CSF leak during the postoperative phase remains challenging. Although rare, early clinical suspicion must be considered to establish the diagnosis.

Multiple and recurrent intracranial pseudolymphoma mimicking multiple skull base meningioma, a case report

INTRODUCTION AND IMPORTANCE

Primary central nervous system (CNS) lymphomas (PCNSLs) comprise a heterogeneous subset of intracranial disorders, predominantly of the intraparenchymal high-grade non-Hodgkin's lymphoma. Intracranial pseudolymphoma represents an exceedingly rare entity; as few as 3 reports in the English literature. We describe the first multiple large intracranial pseudolymphomata leading to increased intracranial pressure, visual loss, and recurrence during a short while. It also represents the first report of intracranial pseudolymphoma presented as a skull base tumor.

CASE PRESENTATION

We describe a 67-year-old female suffering from left-sided loss of visual acuity, headache, nausea, vomiting, and improper balance. Axial brain computed tomography (CT) scan revealed an isodense anterior interhemispheric mass lesion with surrounding edema in both frontal lobes. T1 and T2 weighted magnetic resonance imaging (MRI) and T1 weighted with gadolinium injection revealed two extra-axial isointense dural-based mass lesions with homogenous enhancement compressing both frontal lobes. The morphologic findings favored B cell pseudolymphoma and meningeal B cell lymphoid hyperplasia. One year later, she developed headaches, disorientation, and progressive meaningless speech lasting 2 months. Subsequent MRI demonstrated the rapid growth of the lesion of the lesser sphenoid wing and recurrence of the lesion at the same site of surgery, thereby undergoing revision surgery in which both tumors were maximally resected using a pterional approach.

CLINICAL DISCUSSION

Intracranial pseudolymphoma remains exceedingly rare, and despite its benign cellular nature, it may proliferate and recur quickly.

CONCLUSION

Intracranial pseudolymphoma should always be considered a rare but potentially differential diagnosis leading to the intraventricular lesion.

Rathke’s cleft cysts: A single-center case series

Background:

Rathke’s cleft cysts (RCCs) are common benign sellar or suprasellar lesions. The aim of this study is to report our experience on the management of 27 RCC cases.

Methods:

We retrospectively analyzed a series of 27 patients with symptomatic RCC who were referred to our department between January 2016 and January 2020. Data regarding patients’ demographics, clinical evaluations, laboratory and neuroimaging findings, pathologic records, surgical treatment, and complications were extracted from our electronic database. All patients underwent RCC removal through a direct endoscopic endonasal transsphenoidal (EETS) approach, except for two cases.

Results:

Data of 27 patients (3 men and 24 women; mean age: 38 years) with symptomatic RCC were reviewed. The most common presenting symptom was headache, occurring in 20 (74.0%) patients. In 16 (59.2%) cases, the tumor was primarily located in the sella turcica. Nine (33.3%) cases exhibited a secondary suprasellar extension.

Conclusion:

Our experience with RCC patients showed that EETS is a safe method of treatment, with minimal recurrence.

Oncogenic Roles of Small Nucleolar RNA Host Gene 7 (SNHG7) Long Noncoding RNA in Human Cancers and Potentials

Long noncoding RNAs (lncRNAs) are a class of noncoding transcripts characterized with more than 200 nucleotides of length. Unlike their names, some short open reading frames are recognized for them encoding small proteins. LncRNAs are found to play regulatory roles in essential cellular processes such as cell growth and apoptosis. Therefore, an increasing number of lncRNAs are identified with dysregulation in a wide variety of human cancers. SNHG7 is an lncRNA with upregulation in cancer cells and tissues. It is frequently reported with potency of promoting malignant cell behaviors in vitro and in vivo. Like oncogenic/tumor suppressor lncRNAs, SNHG7 is found to exert its tumorigenic functions through interaction with other biological substances. These include sponging target miRNAs (various numbers are identified), regulation of several signaling pathways, transcription factors, and effector proteins. Importantly, clinical studies demonstrate association between high SNHG7 expression and clinicopathological features in cancerous patients, worse prognosis, and enhanced chemoresistance. In this review, we summarize recent studies in three eras of cell, animal, and human experiments to bold the prognostic, diagnostic, and therapeutic potentials.

Clinical outcome of selective amygdalectomy in a series of patients with resistant temporal lobe epilepsy

Background:

Selective amygdalohippocampectomy is one of the main approaches for treating medial temporal lobe epilepsy (TLE). We herewith describe seven cases of amygdala lesions treated with selective amygdalectomy with the hippocampus saving procedure. Furthermore, we explain the trans-middle temporal gyrus transventricular approach for selective amygdalectomy.

Methods:

We studied patients with TLE who underwent selective amygdalectomy with hippocampal saving procedure between March 2012 and July 2018. We preferred the trans-middle temporal gyrus transventricular approach. We adopted pterional craniotomy with extensive exposure of the base and posterior of the temporal lobe. The posterior margin of resection in the intraventricular part of the amygdala was considered the inferior choroidal point. Medially anterior part of the uncus was resected until reaching the ambient cistern. We applied the transcortical transventricular approach for selective amygdalectomy in all patients.

Results:

We present 11 cases having an amygdala lesion in our series, seven of whom underwent selective amygdalectomy with hippocampal sparing. Nine patients had neoplastic lesions, and in two of them, gliosis was evident. Total resection of the lesion was achieved in all cases based on postoperative magnetic resonance imaging. No unusual complication or surgically-related new neurological deficit occurred.

Conclusion:

We consider the resection of the amygdala until the inferior choroidal point sufficient for the disconnection of its circuits, which results in more effective control of seizures and reduction of surgery time and complications.

The Emerging Role of Non-Coding RNAs in Osteoarthritis

Osteoarthritis (OS) is the most frequent degenerative condition in the joints, disabling many adults. Several abnormalities in the articular cartilage, subchondral bone, synovial tissue, and meniscus have been detected in the course of OA. Destruction of articular cartilage, the formation of osteophytes, subchondral sclerosis, and hyperplasia of synovial tissue are hallmarks of OA. More recently, several investigations have underscored the regulatory roles of non-coding RNAs (ncRNAs) in OA development. Different classes of non-coding RNAs, including long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), have been reported to affect the development of OA. The expression level of these transcripts has also been used as diagnostic tools in OA. In the present article, we aimed at reporting the role of these transcripts in this process. We need to give a specific angle on the pathology to provide meaningful thoughts on it.

CircMTO1: A circular RNA with roles in the carcinogenesis

Circular RNAs (circRNAs) have a closed loop structure which endows them high stability. These transcripts are made through back splicing instead of classical splicing and are abundant in the human transcriptome. Recent advances in the development and implementation of high-throughput sequencing methods in cooperation with novel bioinformatics tools have shown contribution of circRNAs in the developmental processes, physiological settings and pathoetiology of cancers. CircMTO1 is a circRNA which was firstly identified as a down-regulated circRNA in hepatocellular carcinoma through circRNA profiling using microarray technique. Subsequent independent studies in lung adenocarcinoma, colorectal cancer, bladder cancer, glioblastoma, prostate cancer, osteosarcoma, gastric cancer and ovarian cancer have verified down-regulation of circMTO1 in neoplastic tissues compared with non-neoplastic ones. However, expression of circMTO1 has been found to be up-regulated in cervical and gallbladder cancers. miR-17, miR-9, miR-221, miR-6893, miR-92, miR-219a-5p, miR-337, miR-630, miR-3200-5p and miR-199a-3p have been shown to be sequestered by circMTO1. This circRNA can regulate activity of Notch, Wnt/β-Catenin, TGF-β/Smad, JAK1/STAT3 and AMPK signaling pathways. In the current study, we review the literature on the role of circMTO1 in the tumorigenesis.

Prepontine arachnoid cyst presenting with headache and diplopia: A case report study

Background:

Arachnoid cysts are found everywhere in cerebrospinal axis, most often in the middle cranial fossa. They are very rare in prepontine location.

Case Description:

In this study, we report a 26-year-old female presenting with a 3-month history of headache and diplopia. On physical examination, she had clinical manifestations of sixth cranial nerve palsy. Magnetic resonance imaging revealed a prepontine arachnoid cyst with extension into interpeduncular and suprasellar cisterns. Computed tomography scan demonstrated no evidence of hydrocephalus. The patient was treated surgically by endoscopic fenestration of the cyst with endonasal transsphenoidal approach. The cyst was opened to prepontine, interpeduncular, and suprasellar cisterns.

Conclusion:

Endoscopic endonasal fenestration of the cyst to adjacent cistern may be safe in prepontine arachnoid cysts with sellar and suprasellar extension; it may be effective and less invasive compare to transcranial approach.

Solitary aneurysm of the filum terminale artery: A case report and review of the literature

BACKGROUND

We report a rare case of aneurysmal dilatation of filum terminale artery after resection of filum terminal myxopapillary ependymoma.

CASE DESCRIPTION

The authors report a rare aneurysmal dilatation of the filum terminale artery following removal of a filum terminal myxopapillary ependymoma in a 10-year-old male. The patient presented with 6-month history of increasing back pain without a focal neurological deficit. Magnetic resonance (MR) showed an intradural filum terminale lesion that was completely excised. Three months later, the MR again revealed a lesion involving the filum terminale. During the second surgery, however, an aneurysmal dilation of the filum artery was found, which was coagulated and resected. Following the secondary surgery, the patient's symptoms gradually resolved, and he remains intact.

CONCLUSION

Although rare, a true aneurysm after spinal surgery should be considered among the differential diagnostic consideration in the region of the filum terminale.