Reconversion of neurosurgical practice in times of the SARS-CoV-2 pandemic: a narrative review of the literature and guideline implementation in a Mexican neurosurgical referral center.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has forced the modification of surgical practice worldwide. Medical centers have been adapted to provide an efficient arrangement of their economic and human resources. Although neurosurgeons are not in the first line of management and treatment of COVID-19 patients, they take care of patients with neurological pathology and potential severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, the authors describe their institutional actions against the pandemic and compare these actions with those in peer-reviewed publications. METHODS: The authors conducted a search using the MEDLINE, PubMed, and Google Scholar databases from the beginning of the pandemic until July 11, 2020, using the following terms: "Neurosurgery," "COVID-19/SARS-CoV-2," "reconversion/modification," "practice," "academy," and "teaching." Then, they created operational guidelines tailored for their institution to maximize resource efficiency and minimize risk for the healthcare personnel. RESULTS: According to the reviewed literature, the authors defined the following three changes that have had the greatest impact in neurosurgical practice during the COVID-19 pandemic: 1) changes in clinical practices; 2) changes in the medical care setting, including modifications of perioperative care; and 3) changes in the academic teaching methodology. CONCLUSIONS: The Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez" is one of the major referral centers for treating highly complex neurosurgical pathologies in Mexico. Its clinical and neurosurgical practices have been modified with the implementation of specific interventions against the spread of COVID-19. These practical and simple actions are remarkably relevant in the context of the pandemic and can be adopted and suited by other healthcare centers according to their available resources to better prepare for the next event.

Antimicrobial resistance and antibiotic consumption in Mexican hospitals.

OBJECTIVE: To establish the current situation of antimicrobial resistance and antibiotic consumption in Mexican hospitals. MATERIALS AND METHODS: Antimicrobial susceptibility data from blood and urine isolates were collected. Defined daily dose (DDD) of antibiotic consumption/100 occupied beds (OBD) was calculated. RESULTS: Study period: 2016 and 2017. Of 4 382 blood isolates, E. coli and K. pneumoniae were most frequently reported, with antimicrobial resistance >30% for most drugs tested, only for carbapenems and amikacin resistance were <20%. A. baumannii had antimicrobial resistance >20% to all drugs. Resistance to oxacillin in S. aureus was 20%. From 12 151 urine isolates, 90% corresponded to E. coli; resistance to ciprofloxacin, cephalosporins and trimethoprim/sulfamethoxazole was >50%, with good susceptibility to nitrofurantoin, amikacin and carbapenems. Global median antimicrobial consumption was 57.2 DDD/100 OB. CONCLUSIONS: s. This report shows a high antimicrobial resistance level in Gram-negative bacilli and provides an insight into the seriousness of the problem of antibiotic consumption.

OBJETIVO: Establecer la situación actual de la resistencia antimicrobiana y el consumo de antibióticos en hospitales mexicanos. MATERIAL Y MÉTODOS: Se colectaron datos de susceptibilidad antimicrobiana de aislamientos de sangre y orina. Se calculó la dosis diaria definida (DDD) del consumo de antibióticos/100 estancias. RESULTADOS: Periodo de estudio de 2016 a 2017. De 4 382 aislamientos en sangre, E. coli y K. pneumoniae fueron las más frecuentes, con resistencia >30% a la mayoría de las drogas evaluadas; sólo para carbapenémicos y amikacina la resistencia fue <20%. A. baumannii tuvo resistencia >20% a todos los fármacos. La resistencia a oxacilina en S. aureus fue de 20%. De 12 151 aislamientos en urocultivos, 90% correspondió a E. coli; la resistencia a ciprofloxacina, cefalosporinas y trimetoprima/sulfametoxazol fue >50%, con buena susceptibilidad a nitrofurantoína, amikacina y carbapenémicos. La mediana del consumo global de antibióticos en DDD/100 estancias fue de 57.2. CONCLUSIONES: Este reporte muestra el nivel elevado de resistencia en bacilos Gram-negativos y brinda una perspectiva de la gravedad del problema del consumo de antibióticos.

Spinal Taenia solium cysticercosis in Mexican and Indian patients: a comparison of 30-year experience in two neurological referral centers and review of literature.

OBJECTIVE: To present a retrospective study from patients with spinal cysticercosis (SC), diagnosed within the last 30 years in Mexican and Indian neurological referral centers. METHODS: This is a retrospective and comparative study of the clinical and radiological profile between Mexican and Indian patients with spinal neurocysticercosis during a 30-year period and a review of the literature during the same period. RESULTS: Twenty-seven SC patients were included: 19 from Mexico and 8 from India. SC presented predominantly with motor symptoms (21/27 patients): paraparesis and paraplegia were the most common signs; one-third of patients presented sphincter dysfunction. Imaging studies showed that parasites in vesicular stage were more frequent in patients from Mexico, while degenerative stages predominated in India. Association of subarachnoid cysticerci and hydrocephalus was observed only in Mexican patients. CONCLUSIONS: Despite the limitations of this study, the collected information supports the existence of differences in the clinical and radiological traits of SC patients between Asian and Latin-American hospitals. The possible biological factors that may underlie these differences are discussed.

Intrathecal gadodiamide for identifying subarachnoid and ventricular neurocysticercosis.

OBJECTIVE: Some neurocysticercosis cysts may remain hidden despite novel MRI sequences. This study evaluates the diagnostic value of gadodiamide (GDD)-contrasted MRI cisternography in selected cases of neurocysticercosis. METHODS: We included patients aged 18-65 years with a probable diagnosis of subarachnoid cysticercosis in whom previous neuroimaging studies failed to demonstrate the presence of cysts. One millilitre of GDD was administered intrathecally as a contrast agent with subsequent performance of MRI. RESULTS: Fourteen patients were included. Optimal contrast diffusion was achieved in nine patients, and partial diffusion was achieved in 4. Intracranial vesicles were identified in 10 patients, with the presence of more than 60 basal subarachnoid vesicles being revealed in all, with five cysts in the fourth ventricle in four patients and a floating cyst in the lateral ventricle in one. In one case, intrathecal GDD demonstrated spinal cysticercosis. No adverse events were reported after intrathecal GDD administration. CONCLUSIONS: Intrathecal GDD administration is useful for the diagnosis of subarachnoid and intraventricular neurocysticercosis and can be used to improve diagnostic accuracy in selected cases.

[Liver abscess syndrome with lung involvement secondary to hypermucoviscosity Klebsiella pneumoniae]. / Síndrome de absceso hepático secundario a Klebsiella pneumoniae hipermucoviscosa con involucro pulmonar.

Klebsiella pneumoniae liver abscess syndrome (KLAS) is an emerging infection characterized by primary monomicrobial liver abscess, bacteremia and metastatic complications. KLAS is endemic in Taiwan but additional cases has also been described in other world regions. It's caused by strains of K. pneumonia serotype K1, rmpA, magA positive, displaying hypermucoviscosity. We present the case of a previously healthy 69 years old patient who developed fever, liver abscess,septic shock, bacteremia, and pneumonia. In cultures grew hypermucoviscous phenotype of K. pneumonia characterized by positive "string test". The patient responded favourably to antibiotic therapy with ceftriaxone, meropenem, amykacin and percutaneous drainage of the abscess. Increased awareness about this globally emerging infection by physicians could allow earlier detection and optimal treatment.

Endoscopic endonasal resection of a Drechslera hawaiiensis sphenoid fungal ball.

Background: Fungal infections should always be considered in difficult-to-treat paranasal sinus conditions. Sphenoid fungal balls are characterized by the presence of dense fungal masses in the sinus cavity without invasion of surrounding tissues. This case emphasizes the importance of accurate terminology and management and also highlights the involvement of rare pathogens such as Drechslera hawaiiensis. Diagnosis is typically based on imaging studies and intraoperative findings. Accurate identification of the pathogen is crucial. Fungal infections of the paranasal sinuses, including fungus balls, can present challenges in diagnosis and treatment. D. hawaiiensis, although infrequent, can cause potential life-threatening infections. Case Description: We present a 26-year-old non-HIV male patient who presented with nasal symptoms and mild headaches. The patient underwent an endoscopic exploration that revealed a soft, grayish lesion with a buttery consistency. Gross total resection was achieved and the lesion was identified as being caused by D. hawaiiensis; thus, intravenous antifungal treatment was given. Conclusion: Endoscopic surgery remains the preferred approach for disease control. Considering alternative treatments and exploring novel approaches are essential in managing complex pathologies in neurosurgical practice.

Cryptococcal Meningitis in a Mexican Neurological Center.

BACKGROUND: Cryptococcal meningitis, one of the most severe infections affecting the central nervous system, often involves severe neurological sequels and high mortality. METHODS: A retrospective review was performed, including 76 cases admitted in a 10-year period at a neurological referral center in Mexico City. From 68 isolates, 52 fungal specimens were identified as part of the Cryptococcus neoformans var. neoformans complex, 15 as C. neoformans var gattii complex, and one as Cryptococcus non- neoformans/gattii . RESULTS: Higher cryptococcal meningitis incidence and severity were found in HIV-infected men; other risk factors frequently observed were diabetes mellitus and labor exposure to poultry. The main clinical manifestations were subacute headache, cognitive alterations, and photophobia (exclusively in HIV patients). MRI was highly sensitive for pathologic findings such as meningeal enhancements and cryptococcomas, most of them associated to C. neoformans complex. Eleven patients developed severe brain vasculitis, as observed by transcranial Doppler. Hydrocephalus with intracranial hypertension was the most frequent complication. CONCLUSIONS: One-half of the population died, and the rest had neurological sequels, mainly neuropsychiatric manifestations and secondary headaches. These patients developed severe functional limitations in performing daily activities in an independent manner.

The Real Practice Prescribing Antibiotics in Outpatients: A Failed Control Case Assessed through the Simulated Patient Method.

The first level of medical care provides the largest number of consultations for the most frequent diseases at the community level, including acute pharyngitis (AP), acute diarrhoea (AD) and uncomplicated acute urinary tract infections (UAUTIs). The inappropriate use of antibiotics in these diseases represents a high risk for the generation of antimicrobial resistance (AMR) in bacteria causing community infections. To evaluate the patterns of medical prescription for these diseases in medical offices adjacent to pharmacies, we used an adult simulated patient (SP) method representing the three diseases, AP, AD and UAUTI. Each person played a role in one of the three diseases, with the signs and symptoms described in the national clinical practice guidelines (CPGs). Diagnostic accuracy and therapeutic management were assessed. Information from 280 consultations in the Mexico City area was obtained. For the 101 AP consultations, in 90 cases (89.1%), one or more antibiotics or antivirals were prescribed; for the 127 AD, in 104 cases (81.8%), one or more antiparasitic drugs or intestinal antiseptics were prescribed; for the scenarios involving UAUTIs in adult women, in 51 of 52 cases (98.1%) one antibiotic was prescribed. The antibiotic group with the highest prescription pattern for AP, AD and UAUTIs was aminopenicillins and benzylpenicillins [27/90 (30%)], co-trimoxazole [35/104 (27.6%)] and quinolones [38/51 (73.1%)], respectively. Our findings reveal the highly inappropriate use of antibiotics for AP and AD in a sector of the first level of health care, which could be a widespread phenomenon at the regional and national level and highlights the urgent need to update antibiotic prescriptions for UAUTIs according to local resistance patterns. Supervision of adherence to the CPGs is needed, as well as raising awareness about the rational use of antibiotics and the threat posed by AMR at the first level of care.

The Impact of the COVID-19 Pandemic in Postoperative Neurosurgical Infections at a Reference Center in México.

The COVID-19 pandemic has had a major global impact on the treatment of hospitalized surgical patients. Our study retrospectively evaluates the impact of the COVID-19 pandemic at a neurosurgical reference center in Mexico City. We compared the number of neurosurgeries, the rate and type of postoperative infections, the causative microorganisms and in-hospital mortality rates in a 4-year period, from the pre-pandemic year 2019 until 2022. A total of 4150 neurosurgical procedures were registered. In 2020 the total number of surgeries was reduced by 36% compared to 2019 OR = 0.689 (95% CI 0.566-0.834) p ≤ 0.001, transnasal/trans sphenoidal pituitary resections decreased by 53%, and spinal surgeries by 52%. The rate of neurosurgical infections increased from 3.5% in 2019 to 5.6% in 2020 (p = 0.002). Regarding the microorganisms that caused infections, gram positive cocci accounted for 43.5% of isolates, Klebsiella spp. and Pseudomonas spp. caused one third of the infections. No significant differences were found for in-hospital mortality nor patterns of resistance to antibiotics. The number of surgeries increased in the last two years, although the infection rate has returned to pre-pandemic levels. We observed a lower impact from subsequent waves of COVID-19 and despite an increase in the number of surgeries, the surgeries have not amounted to the full pre-pandemic levels.

A life-threatening central nervous system-tuberculosis inflammatory reaction nonresponsive to corticosteroids and successfully controlled by infliximab in a young patient with a variant of juvenile idiopathic arthritis.

We report a young patient with a variant of juvenile idiopathic arthritis, who, after 4 years of infliximab treatment, developed miliary tuberculosis (TB) with central nervous system involvement (meningitis and multiple tuberculomas). After anti-TB treatment, clinical and radiologic responses were observed, but severe cerebrospinal fluid and brain inflammatory reaction, nonresponsive to corticosteroids, persisted. It was considered a life-threatening paradoxical reaction based on initial cerebrospinal fluid isolation of Mycobacterium tuberculosis fully sensitive to primary anti-TB drugs. After 4 months in the hospital, infliximab was administered considering that infliximab is a potent tumor necrosis factor α inhibiting agent that participates in the formation and preservation of granulomas and may help to modulate the exaggerated cell-mediated immune response against mycobacterial antigens. Clinical complications associated to brain inflammation resolved, and after 3 years of follow-up, the patient remains self-sufficient without neurologic sequels.

The management of primary central nervous system lymphoma related to AIDS in the HAART era.

PURPOSE OF REVIEW: The review highlights the recent advances in the pathogenesis, diagnosis and treatment of AIDS-related primary CNS lymphoma (AIDS-PCNSL). RECENT FINDINGS: The incidence of AIDS-PCNSL has decreased in the era of highly active antiretroviral therapy (HAART). The prognosis has improved and this most probably in relation both with the HAART-induced immunologic status recovery and subsequently the possibility to use more aggressive treatment strategies. Immunomodulatory effect of HAART seems also to have an indirect antitumor activity on the disease. SUMMARY: The treatment strategy for AIDS-PCNSL in the HAART era tends to become similar to that of the immunocompetent population. In the absence of randomized trials devoted to AIDS-PCNSL, most current national comprehensive cancer network guidelines recommend the use of high-dose methotrexate-based chemotherapy combined or not with whole-brain radiotherapy as initial treatment in addition to HAART. The objective for the future would be that prognosis of AIDS-PCNSL catch up with that of the immunocompetent patients with special attention to systemic and neurocognitive tolerance of the treatments.

COVID-19: Clouds Over the Antimicrobial Resistance Landscape.

In recent years, the increase in antimicrobial resistance (AMR) has been recognized as a real threat to human and animal health. It is a problem that has been given the highest priority, uniting nations in the fight against its causes and effects. Among the actions that have been implemented are: clinical and microbiological surveillance, promotion of rational and controlled use of antibiotics, AMR stewardship programs in hospitals, development of tools for rapid diagnosis of infectious diseases to establish prompt and adequate treatment, and radically improving vaccination strategies. The current COVID-19 pandemic has placed disproportionate demands on the healthcare infrastructure and economy worldwide, which will negatively impact on the availability of materials as well as the technical capacity for diagnosis, patient care, and treatment of both COVID-19 and non-COVID-19 patients. Disruptions to production and distribution chains will hamper the availability and usage of antibiotics, also interrupting several of the activities that have been implemented thus far to combat AMR, including detailed laboratory monitoring and reinforced vaccination programs. Here, we discuss the main aspects that should be considered with regard to AMR, that may be affected by the pandemic and propose some actions to counter them.

Free Area of the Spinal Canal and Torg's Ratio in Acute Cervical Trauma and Degenerative Disease: MANCOVA and Correlational Analyses.

BACKGROUND: The two of the most common indications for magnetic resonance (MR) imaging of the cervical spine include acute spine trauma and degenerative disease. OBJECTIVE: We aimed to correlate the measurements of the free area of the spinal canal (FASC), a new approach to the cervical spinal canal compromise, with the Torg´s ratio quantification of the cervical spine. METHODS: A cross-sectional study including 50 cervical-spine MR evaluations of patients with acute cervical trauma or degenerative disease was performed. We used multivariate analysis of covariance (MANCOVA) to identify the type of lesion, intervertebral level and gender differences between FASC and Torg´s ratio quantification of the cervical spine; age was the controlled covariate. Correlates between FASC and Torg´s ratio were obtained at each intervertebral level. RESULTS: There was a non-significant interaction between the type of lesion, gender and intervertebral levels between FASC and Torg´s ratio measurements, F (8, 456) 0.260, p = .978; Wilks' Lambda 0.991; with a small effect size (partial η2 = .005). Among the main effects, only the gender was statistically significant: F (2, 228) = 3.682, p = .027. The age (controlled covariate) was non-significantly related to FASC and Torg´s ratio quantification: F (2, 228) = .098, p = .907. The Pearson´s correlation coefficient depicted a poor, non-significant agreement between FASC and Torg´s ratio. CONCLUSION: FASC provides an integrative evaluation of the cervical spinal canal compromise in acute, cervical spine trauma and degenerative disease. Further observations and correlation with specific neurological symptoms, surgical findings and clinical outcomes are necessary to assess the usefulness of FASC in clinical settings.

Phenotype of Peripheral NK Cells in Latent, Active, and Meningeal Tuberculosis.

The mechanisms underlying the immunopathology of tuberculous meningitis (TBM), the most severe clinical form of extrapulmonary tuberculosis (TB), are not understood. It is currently believed that the spread of Mycobacterium tuberculosis (Mtb) from the lung is an early event that occurs before the establishment of adaptive immunity. Hence, several innate immune mechanisms may participate in the containment of Mtb infection and prevent extrapulmonary disease manifestations. Natural killer (NK) cells participate in defensive processes that distinguish latent TB infection (LTBI) from active pulmonary TB (PTB). However, their role in TBM is unknown. Here, we performed a cross-sectional analysis of circulating NK cellCID="C008" value="s" phenotype in a prospective cohort of TBM patients (n = 10) using flow cytometry. Also, we addressed the responses of memory-like NK cell subpopulations to the contact with Mtb antigens in vitro. Finally, we determined plasma levels of soluble NKG2D receptor ligands in our cohort of TBM patients by enzyme-linked immunosorbent assay (ELISA). Our comparative groups consisted of individuals with LTBI (n = 11) and PTB (n = 27) patients. We found that NK cells from TBM patients showed lower absolute frequencies, higher CD69 expression, and poor expansion of the CD45RO+ memory-like subpopulation upon Mtb exposure in vitro compared to LTBI individuals. In addition, a reduction in the frequency of CD56brightCD16- NK cells characterized TBM patients but not LTBI or PTB subjects. Our study expands on earlier reports about the role of NK cells in TBM showing a reduced frequency of cytokine-producing cells compared to LTBI and PTB.

Multidrug-resistant Klebsiella oxytoca ventriculitis, successfully treated with intraventricular tigecycline: A case report.

A 38-year-old male presented to the hospital with headache, fever, and meningeal signs. He had undergone a surgical review of a ventriculoperitoneal shunt system one month earlier. A head computed tomography scan showed hydrocephalus. His medical history included a human immunodeficiency virus infection identified four years before and resolved cryptococcal meningitis, which had necessitated the implantation of the shunt system. Ventricular cerebrospinal fluid (CSF) was obtained, which showed inflammation and, in culture, grew a Gram-negative bacillus identified as multidrug-resistant Klebsiella oxytoca. The shunt was removed and a ventricular drain was installed. Treatment with meropenem and amikacin was established without a response; the CSF white blood cell count continued to increase, with cultures remaining positive. The patient's clinical condition deteriorated to stupor. With informed consent, intraventricular (ITV) treatment with tigecycline was initiated at a dose of 5 mg every 24 h and, three days later, the CSF cultures were negativized. Tigecycline levels in the CSF were quantified by liquid chromatography with ultraviolet detection and showed peak concentrations achieved at two hours after the dose of between 178 and 310 µg/mL. After 11 days of treatment with ITV tigecycline and eight negative CSF cultures, a new CSF shunt was installed. During follow-up review 10 months later, the patient reported he was working. The dose of tigecycline used in this study produced levels 15 to 20 times the minimum inhibitory concentration of the bacteria for up to six hours with adequate tolerance.

Coccidioidal meningitis in non-AIDS patients. A case series at a Mexican neurological referral center.

BACKGROUND: Coccidioidal meningitis is a life-threatening condition and a diagnostic challenge in cases of chronic meningitis. It is associated to severe complications, like basal arachnoiditis, hydrocephalus, and secondary vasculitis. OBJECTIVE: To present a 20-year retrospective clinical series of coccidioidal meningitis cases at a Mexican neurological referral center. RESULTS: The clinical records of 11 patients, predominantly males, were retrieved. Weight loss and night sweats were observed in 64 % of cases. Neurological signs included intracranial hypertension in 91 % of cases, altered alertness and meningeal syndrome in 72 %, and neuropsychiatric symptoms in 64 %. Mean CSF glucose levels were 30 ± 25 mg/dL, and pleocytosis ranged from 0 to 2218 cells/mm3. The diagnosis was confirmed by coccidioidal antigen latex agglutination in 91 % of cases. Radiological findings were hepatomegaly in 55 % of cases and pneumonia in 45 %. Neuroimaging findings included leptomeningitis in 73 % of cases, pachymeningitis in 45 %, and vascular involvement in 91 %. Less common findings included spinal cord lesion and mycotic aneurism, found in 18 % of cases. A molecular coccidioidal DNA test confirmed the predominance of Coccidioides immitis, detected in 64 % of cases. With respect to the clinical outcome, 46 % of patients died. The survivors suffered from sequels like chronic headache, cognitive alterations, and depression. CONCLUSIONS: Coccidioidal meningitis is an entity with high mortality rates. More than one half of patients suffered disseminated disease. Although meningeal signs are not frequent in chronic meningitis, more than two-thirds of our patients showed mild nuchal rigidity. In addition, cerebral and cerebellar volume loss, associated with cognitive impairment and depression, was often observed in surviving patients during the clinical-radiological follow-up.

Fungal mycotic aneurysm in a patient with Aspergillus terreus chronic meningoencephalitis.

BACKGROUND: Central nervous system involvement due to aspergillosis is an extremely serious entity, particularly in patients with severe neutropenia, hematological diseases, or post-transplant cases. Immunocompetent patients can be infected by intense exposure, particularly iatrogenic after invasive procedures. CASE DESCRIPTION: We present the case of a 26-year-old male with a 1 year appendectomy background, which required epidural anesthesia. After that surgery, insidious headache presented, requiring mild analgesics for adequate control. In the following weeks, headaches increased and tomographic imaging revealed hydrocephalus. A ventriculoperitoneal shunt was placed, and empirical treatment for neurocysticercosis was established, but diagnosis was never confirmed. Sequentially, shunt dysfunction occurred twice, for which shunt replacement was performed. Cerebrospinal fluid and shunt's catheter were cultured. Some days later, a filamentous fungus was isolated and finally identified as Aspergillus sp. Intravenous amphotericin B and fluconazole at therapeutic dosage were administered; however, a torpid clinical evolution was observed. After a 2-week antifungal scheme, the fungus was identified as Aspergillus terreus. The patient developed sudden rostrocaudal deterioration. Computed tomography imaging was done, revealing a 70 cc hematoma in the right operculoinsular region, midline shift, and a 9 mm saccular aneurysm at the bifurcation of the middle cerebral artery. CONCLUSION: Cerebral aspergillosis is a serious disease with high mortality in patients, particularly those without identifiable risk factors. The iatrogenic forms are serious, due to the delay of clinical diagnosis. It is important to have a high index of suspicion in patients with a history of invasive procedures such as epidural anesthesia or surgery, and who develop a persistent chronic headache or chronic meningitis.

Dopaminergic Hyperactivity in Neurological Patients with Delirium.

BACKGROUND: Delirium has important etiological, prognostic, and therapeutic implications. The study of neurochemical markers in this condition is relevant to the understanding of its pathophysiology. The assessment of the dopamine system is particularly relevant, as dopamine antagonists are the most used drugs in delirium. AIM: To analyze neurotransmission markers in patients with delirium, focusing in the dopamine metabolite, homovanillic acid. METHODS: A case-control study was performed at the National Institute of Neurology and Neurosurgery, Mexico, including hospitalized patients in which lumbar puncture was obtained for diagnostic purposes. Cases were selected if they fulfilled DSM-5 criteria for delirium. Age-paired controls were patients in which delirium was ruled out, selected at the same clinical scenario, during the same period. Neurological and systemic diagnoses were registered. Delirium was assessed using the DRS-98-R instrument. The dopamine metabolite, homovanillic acid (HVA), was measured by means of high-performance liquid chromatography. Other neurotransmission markers were also measured (5-hydroxyindoleacetic acid, glutamate, aspartate, GABA, glycine, arginine, citrulline, nitrites, and nitrates). A logistic regression model was used to determine pathogenic factors associated with the presence of delirium. RESULTS: 68 neurological patients with delirium and 68 patients without delirium were included. Higher homovanillic acid levels in cerebrospinal fluid were significantly associated with delirium. This result was significant after a subanalysis in patients without exposure to antipsychotics. Male gender and autoimmune limbic encephalitis were also associated with the presence of delirium. CONCLUSIONS: In hospitalized neurological patients, dopaminergic hyperactivity and autoimmune limbic encephalitis are pathogenic factors associated with the presence of delirium.

Guillain-Barré Syndrome Associated With Zika Virus Infection: A Prospective Case Series From Mexico.

Background: On May 2016, anticipating the rainy season from June to October in Mexico, we expected an increase in cases of Zika virus (ZIKV) infections. With the goal of identifying cases of GBS associated with ZIKV infection, a prospective joint study was conducted by a reference center for neurological patients and the Secretary of Health in Mexico City from July 2016 to November 2016. Methods: Serum, cerebrospinal fluid, urine, and saliva were tested by RT-PCR for ZIKV, dengue virus, and chikungunya virus in patients referred from states with reported transmissions of ZIKV infection, and with clinical symptoms of GBS according to the Brighton Collaboration criteria. Clinical, electrophysiological, and long-term disability data were collected. Results: In the year 2016 twenty-eight patients with GBS were diagnosed at our institute. In five hospitalized patients with GBS, RT-PCR was positive to ZIKV in any collected specimen. Dengue and chikungunya RT-PCR results were negative. All five patients had areflexic flaccid weakness, and cranial nerves affected in three. Electrophysiological patterns were demyelinating in two patients and axonal in three. Three patients were discharged improved in 10 days or less, and two patients required intensive care unit admission, and completely recovered during follow-up. Conclusion: Our results are similar to those reported from the state of Veracruz, Mexico, in which out of 33 samples of urine of patients with GBS two had a positive RT-PCR for ZIKV. Simultaneous processing of serum, CSF, urine, and saliva by RT-PCR may increase the success of diagnosis of GBS associated to ZIKV.