Cryptococcal Infection of the Ventriculoperitoneal Shunt in an Immunocompetent Patient

A Rare Complication of Proteus Brain Abscess Due to Coccidioidomycosis Causing Hydrocephalus

Proteus mirabilis is a very common gram-negative facultative anaerobe seen in urinary tract infections. This rod-shaped bacterium tends to cause urolithiasis via its ability to alkalinize the urine. However, in some cases, this bacterium has been shown to cause bacteremia as well as other complicated infections. Here we would like to present a rare case of Proteus mirabilis that has invaded the brain in a patient that has a ventriculoperitoneal (VP) shunt placed due to coccidioidal meningitis causing hydrocephalus. We would also like to discuss the importance of the monitoring of VP shunt and discuss their likelihood of infections and the medical as well as surgical management.

Ventriculoperitoneal shunt infection by Cryptococcus neoformans sensu stricto: Case report and literature review

BACKGROUND

Cryptococcal ventriculoperitoneal shunt infection is known to occur due to an underlying infection in the patient rather than by nosocomial transmission of Cryptococcus during shunt placement. A case of chronic hydrocephalus due to cryptococcal meningitis that was misdiagnosed as tuberculous meningitis is described.

CASE REPORT

Patient details were extracted from charts and laboratory records. The identification of the isolate was confirmed by PCR-restriction fragment length polymorphism of the orotodine monophosphate pyrophosphorylase (URA5) gene. Antifungal susceptibility was determined using the CLSI M27-A3 broth microdilution method. Besides, a Medline search was performed to review all cases of Cryptococcus ventriculoperitoneal shunt infection. Cryptococcus neoformans sensu stricto (formerly Cryptococcus neoformans var. grubii), mating-type MATα was isolated from the cerebrospinal fluid and external ventricular drain tip. The isolate showed low minimum inhibitory concentrations for voriconazole (0.06mg/l), fluconazole (8mg/l), isavuconazole (<0.015mg/l), posaconazole (<0.03mg/l), amphotericin B (<0.06mg/l) and 5-fluorocytosine (1mg/l). The patient was treated with intravenous amphotericin B deoxycholate, but died of cardiopulmonary arrest on the fifteenth postoperative day.

CONCLUSIONS

This report underlines the need to rule out a Cryptococcus infection in those cases of chronic meningitis with hydrocephalus.

Antifungal activity of promethazine and chlorpromazine against planktonic cells and biofilms of Cryptococcus neoformans/Cryptococcus gattii complex species

Cryptococcus neoformans/Cryptococcus gattii are fungal pathogens that affect the central nervous system, mainly in immunocompromised individuals. Due to the limited pharmacological arsenal available for the treatment of cryptococcosis associated with cases of antifungal resistance of Cryptococcus spp. reported in some studies, the search for new compounds with antifungal potential becomes relevant. Thus, the objective of this study was to evaluate the inhibitory effect of phenothiazines (promethazine and chlorpromazine) on C. neoformans/C. gattii planktonic cells and biofilms. In vitro planktonic susceptibility testing was performed using the broth microdilution assay. The effect of phenothiazines was evaluated against biofilm formation and mature Cryptococcus biofilms. Biofilm morphology and ultrastructure were also evaluated by scanning electron microscopy. Promethazine and chlorpromazine showed antifungal activity against planktonic cells, with minimum inhibitory concentrations of 8-32 μg/ml and 4-16 μg/ml, respectively. As for biofilm formation, phenothiazines reduced biomass by 60% and metabolic activity by 90% at 64 μg/ml; while in mature biofilms, reductions of 85% and 90% in biomass and metabolic activity, respectively, were observed at 1024 μg/ml. Promethazine and chlorpromazine were also able to disrupt and fragment biofilms. In conclusion, promethazine and chlorpromazine have antifungal activity against planktonic cells and biofilms of Cryptococcus spp. These data show the potential of promethazine and chlorpromazine as antibiofilm drugs.

Intravitreal Voriconazole for the Treatment of Cryptococcus neoformans Endogenous Endophthalmitis

Background: Cryptococcus neoformans is an encapsulated yeast that can cause fungemia and, in rare instances, lead to endogenous fungal endophthalmitis. No standard of care has been established to treat fungal endophthalmitis when systemic antifungal treatment fails to resolve the intraocular infection. Intravitreal voriconazole has been used for the treatment of fungal endophthalmitis caused by a broad range of fungal pathogens, and a limited number of reports have shown the efficacy of using intravitreal voriconazole for C neoformans endophthalmitis. We report a case of endogenous fungal endophthalmitis caused by C neoformans that was responsive to intravitreal voriconazole. Case Report: A previously healthy 57-year-old male diagnosed with primary neuroendocrine lung tumor developed endogenous endophthalmitis from C neoformans. The endophthalmitis was resistant to intravenous amphotericin B treatment but was responsive to intravenous fluconazole in one eye and was apparently more responsive to intravitreal voriconazole in the other eye. Conclusion: Intravitreal voriconazole should be considered for the treatment of cryptococcal endophthalmitis.

Immune reconstitution inflammatory syndrome following Cryptococcal neoformans infection in an immunocompetent host: A case report and review of the literature

We present a case of Cryptococcus neoformans in an immunocompetent middle-aged woman with a disseminated manifestation of pulmonary cryptoccoma and cryptococcal meningitis resulting in bilateral blindness. The presentation was complicated by delayed diagnosis resulting in optic neuritis and an infected percutaneous lumbar drainage with methicillin resistant staphylococcus aureus (MRSA) and a paradoxical reaction of suspected immune reconstitution inflammatory syndrome (IRIS). We discuss the pathogen, the clinical manifestations and diagnostic approach (through laboratory and radiology findings), differential diagnosis, treatment, and proposed pathogenesis of IRIS and C. neoformans in an immunocompetent patient.

Anti-Cryptococcal activity of a furanone derivative-antibiofilm and opsonophagocytic potential

Cryptococcus neoformans, an encapsulated fungal pathogen is evolving as a major threat to immune-compromised patients and rarely to healthy individuals also. The cell wall bound capsular polysaccharide, melanin pigment and biofilm formation are major virulence factors that are known to contribute to cryptococcal meningitis. In the present study, a furanone derivative, (E)-5-benzylidenedihydrofuran-2(3H)-one (compound-6) was evaluated against biofilm of seven different strains of C. neoformans in melanized and non-melanized condition. In addition, the efficacy of compound-6 in activation of TLR-2, opsonophagocytosis, and modulation of cytokine expression during phagocytosis were studied. During the biofilm study, we found that moderate capsule size favored biofilm formation. Interestingly, the minimum biofilm eradication concentration (MBEC_0.5) of melanized biofilm was found to be achieved at 1- to 1.7-fold higher MBEC_0.5 of non-melanized cells. The maximum eradication of 77% and 69% of non-melanized and melanized biofilm were observed. The capsule size was reduced to half of its size with marked changes in morphology. Furthermore, expression of TLR2, iNOS and pro-inflammatory cytokines such as TNF-α, IL-12, and IFN-γ were also facilitated by compound-6. The correlation analysis showed a positive correlation between phagocytosis and the expression of TLR-2, iNOS, IL-6, IL-12. Collectively, the significant effect of compound-6, anti-melanization activity, antibiofilmand effective immunomodulant could be an interesting dual strategy drug agonist against cryptococcal meningitis.

Delineating the Biofilm Inhibition Mechanisms of Phenolic and Aldehydic Terpenes against Cryptococcus neoformans

The recalcitrant biofilm formed by fungus Cryptococcus neoformans is a life-threatening pathogenic condition responsible for further intensifying cryptococcosis. Considering the enhanced biofilm resistance and toxicity of synthetic antifungal drugs, the search for efficient, nontoxic, and cost-effective natural therapeutics has received a major boost. Phenolic (thymol and carvacrol) and aldehydic (citral) terpenes are natural and safe alternatives capable of efficient microbial biofilm inhibition. However, the biofilm inhibition mechanism of these terpenes still remains unclear. In this study, we adopted an integrative biophysical and biochemical approach to elucidate the hierarchy of their action against C. neoformans biofilm cells. The microscopic analysis revealed disruption of the biofilm cell surface with elevation in surface roughness and reduction in cell height. Although all terpenes acted through ergosterol biosynthesis inhibition, the phenolic terpenes also selectively interacted via ergosterol binding. Further, the alterations in the fatty acid profile in response to terpenes attenuated the cell membrane fluidity with enhanced permeability, resulting in pore formation and efflux of the K+/intracellular content. Additionally, mitochondrial depolarization caused higher levels of reactive oxygen species, which led to increased lipid peroxidation and activation of the antioxidant defense system. Indeed, the oxidative stress caused a significant decline in the amount of extracellular polymeric matrix and capsule sugars (mannose, xylose, and glucuronic acid), leading to a reduced capsule size and an overall negative charge on the cell surface. This comprehensive data revealed the mechanistic insights into the mode of action of terpenes on biofilm inhibition, which could be exploited for formulating novel anti-biofilm agents.

Fungal infections in pediatric neurosurgery

INTRODUCTION

Invasive mycosis of the central nervous system represent a diverse group of diseases that have gradually emerged as not only opportunistic infections in patients with immune susceptibility due to congenital and acquired deficiency, immunomodulation, solid organ and stem cell transplantation, hematological malignancies, and chronic steroid use but also in selected risk populations such as low weight preterm infants, patients with shunted hydrocephalus and external ventricular drainages, skull base surgery, and head injury.

OBJECTIVES

The purpose of this review is to familiarize the pediatric neurosurgeon with the most common mycosis and their clinical scenarios which can be encountered in the clinical practice, with special emphasis on clinical, radiological, and laboratory diagnosis beyond classical microorganism cultures as well as options in medical and surgical treatment given the high incidence of morbidity and mortality associated with these challenging entities.

METHODS

We conducted an online database review (Ovid, PubMed) gathering relevant English language literature published in the last 20 years with special emphasis on recent breakthroughs in the diagnosis and treatment of invasive mycosis of the CNS as well as reported cases within the pediatric neurosurgical literature and their surgical management.

RESULTS

Fungal agents capable of invading the CNS can behave as aggressive entities with rapid progression manifesting as overwhelming meningoencephalitis with vascular compromise or can lead to space-occupying lesions with abscess formation which require prompt diagnosis by either laboratory identification of the components of these biological agents and their host response or by obtaining tissue specimens for microbiological identification which may not be straightforward due to prolonged culture time.

CONCLUSION

Following a high degree of suspicion with prompt initiation of antifungal agents and reversal of potential immunosuppressant therapies along with neurosurgical evacuation of intracranial collections or removal of infected hardware (CSF shunts) can lead to more optimistic outcomes of these complex clinical scenarios.

Undiagnosed Cryptococcus gattii meningitis leading to subsequent ventriculoperitoneal shunt infection in a patient with symptoms of normal pressure hydrocephalus: case report and literature review

Background

Cryptococcus gattii is known to be an etiologic agent of human cryptococcosis, particularly in immunocompetent persons. C. gattii infection usually involves the central nervous system, the respiratory tract, or may be disseminated. Here we report an atypical manifestation of C. gattii infection in a patient who had C. gattii meningitis complicating the ventriculoperitoneal (VP) shunt infection and concurrent infected intraabdominal VP shunt pseudocyst.

Case presentation

A 66-year-old Thai female was initially diagnosed with normal pressure hydrocephalus (NPH) and underwent programmable VP shunt placement. However, she still suffered from recurrent communicating hydrocephalus with in-place VP shunt, and later developed recurrent gait impairment, chronic abdominal pain and abdominal mass. Radiological studies demonstrated recurrent hydrocephalus and a very large intraabdominal VP shunt pseudocyst. C. gattii was isolated from both the cerebrospinal fluid and the pseudocyst aspiration. C. gattii meningitis complicating the VP shunt infection and concurrent infected intraabdominal VP shunt pseudocyst was diagnosed. Prolonged antifungal therapy, removal of the infected VP shunt with subsequent implant of a new shunt provided a good outcome.

Conclusion

Chronic C. gattii meningitis should be aware in a patient presenting with normal pressure hydrocephalus. Under-diagnosed cryptococcal meningitis following VP shunt insertion for treating the hydrocephalus can render a complicated VP shunt infection including infected VP shunt pseudocyst.

Asymptomatic Meningitis and Lung Cavity in a Case of Cryptococcosis

BACKGROUND Cryptococcus neoformans (C. neoformans) infection is one of the most common opportunistic infections in AIDS patients. C. neoformans usually infects the central nervous system (CNS) and/or lungs with typical clinical manifestation. CASE REPORT Here, we report the case of a 52-year-old HIV-1-infected man with disseminated cryptococcosis, including subacute meningitis, pulmonary, and cutaneous cryptococcosis, but only skin lesion served as the chief complaint. Moreover, the results of cerebrospinal fluid (CSF) tests and lung computed tomography (CT) scan were atypical. CONCLUSIONS We present the clinical characteristics of this case and discuss the diagnostic procedure, which will likely help clinicians in making a timely definitive diagnosis of this disease.

Cryptococcal Infection of the Ventriculoperitoneal Shunt in an HIV-Infected Patient with an Excellent Immunovirologic Status

BACKGROUND

Cryptococcus spp. is a rare cause of ventriculoperitoneal shunt (VPS) infection, with a variable clinical presentation. Diagnosis and treatment of this entity are challenging.

CASE DESCRIPTION

A cryptococcal VPS infection occurred in a human immunodeficiency virus-infected patient with an excellent immunovirologic status, with an abdominal mass as the only clinical sign at presentation. Microbiologic diagnosis was confirmed when Cryptococcus neoformans was isolated in 4 cerebrospinal fluid samples on different days. The patient was treated with dual antifungal therapy (liposomal amphotericin B plus flucytosine). The VPS was initially externalized and then removed. At 12-month follow-up, the patient remained asymptomatic, and no replacement VPS was required.

CONCLUSIONS

This is the first reported case of cryptococcal VPS infection in a patient with human immunodeficiency virus infection. Clinical outcome was excellent after dual antifungal therapy plus device withdrawal. Diagnosis and treatment of this entity remain a challenge for clinicians.