Is Neonatal Hyperbilirubinemia Exposure Associated with a Risk of Autism Spectrum Disorder? A Nationwide Cohort Study.

OBJECTIVE: This study aimed to determine whether neonatal hyperbilirubinemia is associated with a risk of autism spectrum disorder (ASD) using a large population-based cohort. STUDY DESIGN: This retrospective cohort study used data from the children's database (2000-2012) of the National Health Insurance Research Database (1996-2012) in Taiwan. We included neonates who were born between 2000 and 2004 and aged <1 month diagnosed with and without hyperbilirubinemia. The primary outcome was physician-diagnosed ASD. At the end of 2012, multivariate Cox's regression analysis was used to estimate hazard ratios (HRs). RESULTS: A total of 67,017 neonates were included. The neonates with hyperbilirubinemia were associated with 1.28-fold increased risk of ASD (HR = 1.28, 95% confidence interval [CI]: 1.05-1.57) compared with those without hyperbilirubinemia. In subanalysis to determine how phototherapy and exchange transfusion treatment for hyperbilirubinemia were associated with ASD showed no association between treatment and ASD, suggesting the lack of a dose-response effect of hyperbilirubinemia on the risk of ASD. Boys had a nearly six-fold higher risk of ASD than girls (HR = 5.89, 95% CI: 4.41-7.86). Additionally, neonates born with preterm birth and low birth weight were associated with a risk of ASD (HR = 1.46, 95% CI: 1.00-2.13). CONCLUSION: We did not observe a dose-response effect of hyperbilirubinemia on ASD, but neonatal hyperbilirubinemia may be an independent risk factor for ASD if there is a residual confounding by other perinatal complications. Therefore, this study does not support a causal link between neonatal hyperbilirubinemia exposure and the risk of ASD.

Epithelial growth factor receptor tyrosine kinase inhibitors alleviate house dust mite allergen Der p2-induced IL-6 and IL-8.

Steroid-insensitive asthma-related airway inflammation is associated with the expression of epidermal growth factor receptor (EGFR) tyrosine kinase in asthmatic bronchial epithelium. Proinflammatory cytokines IL-6 and IL-8 are related to steroid-insensitive asthma. It is currently unknown how EGFR-tyrosine kinase inhibitors (EGFR-TKIs) affects house dust mite (HDM)-induced asthma in terms of inflammatory cytokines related to steroid-resistant asthma and further signaling pathway. Cytokine expressions and EGFR signaling pathway were performed by ELISA, reverse transcriptase PCR, real-time PCR, and Western blot in cell-line models. AMP-activated protein kinase (AMPK) pathway-related inhibitors were applied to confirm the association between EGFR-TKI and AMPK pathway. HDM induced IL-6 and IL-8 in a dose-dependent manner. Both Erlotinib (Tarceva) and Osimertinib (AZD-9291) reduced the levels of HDM-stimulated IL-6 and IL-8 levels in BEAS-2B cells. AZD-9291 was more effective than Erlotinib in inhibiting phospho-EGFR, and downstream phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) and phopho-signal transducer and activator of transcription 3 (p-STAT3) pathway signaling. In addition, AMPK pathway-related inhibitor, Calcium-/calmodulin-dependent protein kinase kinase ß (CaMKKß) inhibitor, down-regulated IL-8, but EGFR-TKI had no effect on AMPK pathway. Our findings highlight EGFR-TKIs, Tarceva, and AZD-9291, attenuate HDM-induced inflammatory IL-6 and IL-8 cytokines via EGFR signaling axis pathway, but not AMPK signaling pathway.

Association between allergic disease, sleep-disordered breathing, and childhood nocturnal enuresis: a population-based case-control study.

BACKGROUND: Little is known about the associations between allergic disease, sleep-disordered breathing (SDB), and childhood nocturnal enuresis (NE). We examined whether allergic disease and SDB were associated with childhood NE. METHODS: Data were assessed from the 2007-2012 Taiwan National Health Insurance Research Database. We enrolled 4308 children aged 5-18 years having NE diagnosis and age- and sex-matched 4308 children as the control group. The odds ratios of NE were calculated to determine an association with preexisting allergic disease and SDB. RESULTS: A total of 8616 children were included in the analysis. Prevalence of allergic diseases and SDB was significantly higher for the NE group than the control group (all p < 0.001). After adjusting odds ratios for potential confounding factors, except asthma, children with allergic rhinitis, atopic dermatitis, allergic conjunctivitis, and obstructive sleep apnea (OSA) had significantly higher odds of NE compared with children never diagnosed. With stratification for sex, girls with allergic rhinitis, atopic dermatitis, allergic conjunctivitis, OSA, and snoring had significantly higher odds of NE, compared with girls never diagnosed. Only boys with allergic rhinitis and OSA were associated with increased odds of NE. With stratification for age, children aged 5-12 years with allergic rhinitis, atopic dermatitis, allergic conjunctivitis, and OSA had significantly higher odds of NE compared with those never diagnosed. Odds of NE increased with the number of comorbid allergic diseases. CONCLUSIONS: Allergic diseases and SDB are associated with increased odds of childhood NE. The odds of NE increased with the number of comorbid allergic diseases present.

Effects of everolimus on tuberous sclerosis complex-associated renal angiomyolipoma: A preliminary report.

AIM: Tuberous sclerosis complex (TSC) presents with multisystem benign neoplasm induced by dysregulation of the mammalian target of rapamycin pathway. This study aimed to examine the effects of oral everolimus at either 2.5 or 5.0 mg daily on the treatment of TSC-associated renal angiomyolipoma (AML). METHODS: Between July 2012 and August 2015, patients with TSC-associated renal AML were selected for everolimus therapy protocol. An oral everolimus starting dose at 2.5 mg was administered daily, and was gradually increased to 5.0 mg daily. All patients were evaluated using magnetic resonance imaging or computed tomography scanning at baseline, 12, 24, and 36 months after the start of treatment for measuring the changes of renal AML mass volume. RESULTS: Eight patients were finally enrolled for analysis in this study. Everolimus treatment had a statistically significant effect on the renal AML volume reduction during follow-up (P < 0.05). Renal AML mass volume reduction rates were 10.5-45.3% in four patients with everolimus 2.5 mg and 40.7-73.1% in four patients with everolimus 5.0 mg daily; the difference was statistically significant between the two groups (P < 0.05). Longitudinal follow-up for response to everolimus showed volume reduction rates to be around 10.5-73.1% in the initial 6-24 months after everolimus treatment, which remained stable during follow-up up to 36 months. CONCLUSION: The results suggest that an oral everolimus is effective and provides a non-invasive way to treat TSC-associated renal AML, and patients are likely to require maintenance therapy to continue to derive benefit.

Association between the growth rate of subependymal giant cell astrocytoma and age in patients with tuberous sclerosis complex.

PURPOSE: The most common neurological complications associated with tuberous sclerosis complex (TSC) include intractable seizures that begin in infancy and subependymal giant cell astrocytoma (SEGA) complicated by hydrocephalus with increasing age. Information on SEGA growth of TSC patients is limited. This study aimed to examine the TSC-SEGA growth rates by periodic neuroimaging. METHODS: This study evaluated the TSC-SEGA growth rates by serial neuroimaging. Fifty-eight patients with TSC underwent systematic evaluation, including a review of medical history and serial brain neuroimaging. RESULTS: While magnetic resonance imaging was more sensitive in detecting cortical tubers than computed tomography (73.1 vs. 0 %, p < 0.001), its efficacy in identifying intracranial lesions was comparable to that of computed tomography (96.2 vs. 100 %, p = 0.658). Significant tumor growth was observed in children (p = 0.012) and adults (p = 0.028) during follow-up periods, respectively (median for children 23.5 months, interquartile range 18-40 months and median for adults 23 months, interquartile range 12-34 months). Further, the SEGA growth rate in children was significantly higher than that in adults (75.6 vs. 16.5 %, p = 0.03). CONCLUSIONS: The results of the study show that SEGA has a significantly higher growth rate in children using serial follow-up brain imaging, suggesting the importance of performing follow-up neuroimaging at yearly intervals in childhood to identify and prevent potential comorbidities.

Nosocomial neonatal legionellosis associated with water in infant formula, Taiwan.

We report 2 cases of neonatal Legionella infection associated with aspiration of contaminated water used in hospitals to make infant formula. The molecular profiles of Legionella strains isolated from samples from the infants and from water dispensers were indistinguishable. Our report highlights the need to consider nosocomial legionellosis among neonates who have respiratory symptoms.

Neurological images and the predictors for neurological sequelae of epidemic herpangina/hand-foot-mouth disease with encephalomyelitis.

Since 1998 in Taiwan, enterovirus (EV) 71 epidemics have caused encephalomyelitis and placed a significant burden on parents and physicians. In this study, we present clinical manifestations, magnetic resonance (MR) imaging findings, and neurological sequelae on epidemic EV-infected patients with encephalomyelitis. Of the 46 patients, 14 patients presented with neurological sequelae; of them, 3 patients suffered from complications of mental regression. Predictors of unfavorable neurological sequelae were myoclonic jerks (> 4 times/night) and pleocytosis (167/µL) of the cerebrospinal fluid (CSF). Results from viral culture and MR imaging indicated that positive identification of EV71 infection was associated significantly with lesions on MR imaging. Our results show that hand-foot-mouth disease carries a higher risk of encephalomyelitis and that frequent myoclonic jerks and pleocytosis of the CSF are risk factors for subsequent neurological sequelae. Positive identification of EV71 might be useful as a predictor of lesions in MR imaging.

Comparison of procalcitonin and different guidelines for first febrile urinary tract infection in children by imaging.

BACKGROUND: We examined the ability of a procalcitonin (PCT) protocol to detect vesicoureteral reflux (VUR) and renal scarring (RS), evaluated procedural costs and radiation burden, and compared four representative guidelines for children with their first febrile urinary tract infection (UTI). METHODS: Children aged ≤2 years with their first febrile UTI who underwent renal ultrasonography (US), acute and late technetium-99m ((99m)Tc)-dimercaptosuccinic acid scan, and voiding cystourethrography were prospectively studied. The representative guidelines applied in a retrospective simulation included the American Academy of Pediatrics (AAP), National Institute of Clinical Excellence, top-down approach (TDA), and Italian Society of Pediatric Nephrology (ISPN). These were compared in terms of ability to detect abnormalities, procedural costs and radiation. RESULTS: Of 278 children analyzed, 172 (61.9%) had acute pyelonephritis. There was VUR in 101 (36.3%) children, including 73 (26.3%) with grades III-V VUR. RS was identified in 75 (27.0%) children. To detect VUR, TDA and PCT had the highest sensitivity for grades I-V VUR (80.2%) and III-V VUR (94.5%), respectively, whereas AAP had the highest specificity for I-V VUR (77.4%) and III-V VUR (78.0%), respectively. TDA and PCT had the highest sensitivity (100%) for detecting RS. The highest cost and radiation dose was associated with TDA, whereas AAP had the least expenditure and radiation exposure. By multivariate analysis, PCT and VUR, especially grades III-V, were independent predictors of RS. CONCLUSIONS: There is no perfect guideline for first febrile UTI children. The PCT protocol has good ability for detecting high-grade VUR and RS. If based on available imaging modalities and reducing cost and radiation burden, clinical suggestions in the AAP guidelines represent a considerable protocol.

Extra-adrenal paraganglioma presenting as acute chest pain mimicking acute myocardial infarction in a 10-year-old boy.

Extraadrenal paragangliomas are rare pediatric tumors with variable symptoms that cause difficultly in diagnosis and delayed treatment. We report the case of a 10-year-old boy who presented to the pediatric emergency department with acute chest pain and dyspnea mimicking a non-ST-segment elevation acute myocardial infarction. He was subsequently found to have an extraadrenal paraganglioma after a series of imaging and laboratory examinations. The mass was subsequently removed, and the diagnosis of extraadrenal paraganglioma was confirmed histologically. Acute coronary syndrome as the presenting feature of extraadrenal paragangliomas in pediatric population is an even rarer clinical entity.

Effect of the fungal immunomodulatory protein FIP-fve on airway inflammation and cytokine production in mouse asthma model.

The allergy is dependent on the balance between Th1 and Th2. The fungal immunodulatory protein (FIP-fve) was isolated from Flammulina velutipes. FIP-fve has been demonstrated to skew the response to Th1 cytokine production. We investigated whether oral administrations of FIP-fve inhibited allergen (OVA)-induced chronic airway inflammation in the mouse asthma model. After intranasal challenge with OVA, the airway inflammation and hyperresponsiveness were determined by bronchoalveolar lavage fluid (BALF) analysis and ELISA assay. Both pre-treated and post-treated with FIP-fve suppressed the airway hyperresponsiveness by methacholine challenge and significantly decreased the number of infiltrating inflammatory cells and Th2 cytokines in bronchoalveolar lavage fluid (BALF) and serum compared with the OVA sensitized mice. In addition, FIP-fve reduced OVA-specific IgE levels in serum. FIP-fve markedly alleviated the OVA-induced airway hyperresponsiveness (AHR) to inhaled methacholine. Based on lung histopathological studies using hematoxylin and Liu's staining, FIP-fve inhibited inflammatory cell infiltration compared with the OVA-sensitized mice. Oral FIP-fve had an anti-inflammatory effect on OVA-induced airway inflammations and might posses the potential for alternative therapy for allergic airway diseases.

Diagnostic performance of procalcitonin for hospitalised children with acute pyelonephritis presenting to the paediatric emergency department.

OBJECTIVES: Urinary tract infection (UTI) is a common bacterial infection in children that can result in permanent renal damage. This study prospectively assessed the diagnostic performance of procalcitonin (PCT) for predicting acute pyelonephritis (APN) among children with febrile UTI presenting to the paediatric emergency department (ED). METHODS: Children aged ≤10 years with febrile UTI admitted to hospital from the paediatric ED were prospectively studied. Blood PCT, C reactive protein (CRP) and white blood cell (WBC) count were measured in the ED. Sensitivity, specificity, predictive values, multilevel likelihood ratios, receiver operating characteristic (ROC) curve analysis and multivariate logistic regression were used to assess quantitative variables for diagnosing APN. RESULTS: The 136 enrolled patients (56 boys and 80 girls; age range 1 month to 10 years) were divided into APN (n=87) and lower UTI (n=49) groups according to (99m)Tc-dimercaptosuccinic acid scan results. The cut-off value for maximum diagnostic performance of PCT was 1.3 ng/ml (sensitivity 86.2%, specificity 89.8%). By multivariate regression analysis, only PCT and CRP were retained as significant predictors of APN. Comparing ROC curves, PCT had a significantly greater area under the curve than CRP, WBC count and fever for differentiating between APN and lower UTI. CONCLUSIONS: PCT has better sensitivity and specificity than CRP and WBC count for distinguishing between APN and lower UTI. PCT is a valuable marker for predicting APN in children with febrile UTI. It may be considered in the initial investigation and therapeutic strategies for children presenting to the ED.

Diagnostic performance of serum interleukin-6 and interleukin-10 levels and clinical predictors in children with rotavirus and norovirus gastroenteritis.

OBJECTIVES: Rotavirus and norovirus are the two most common causes of acute viral gastroenteritis in children. This study aimed to explore the association of serum interleukin-6 (IL-6) and interleukin-10 (IL-10) levels and the clinical features in children with rotavirus and norovirus gastroenteritis. METHODS: This prospective study enrolled 168 acute gastroenteritis patients admitted to a tertiary care center. Peripheral blood samples were collected for IL-6 and IL-10 assays within the first 72 h of illness. The diagnostic performance of clinical tests was estimated using the receiver operating characteristic (ROC) analysis. Binary logistic regression modeling was performed to examine the predictive variables. RESULTS: Serum IL-6 and IL-10 were measured in children with rotavirus infection (n=30), norovirus infection (n=25), Salmonella infection (n=26), and in 11 healthy controls. There were significant higher degrees of severity of illness and levels of IL-10 in the rotavirus group as compared to the norovirus group. The binary logistic regression analysis revealed that both the ANC and maximum body temperature (BT) were significant clinical predictors for discriminating rotavirus and norovirus gastroenteritis. The ROC curve to evaluate the accuracy of logistic regression model had an AUC of 0.847 (95% CI: 0.741-0.952, p<0.001). CONCLUSIONS: IL-10 shows a significant discriminating ability between rotavirus and norovirus infection. A model incorporating maximum BT and ANC can help pediatricians to distinguish between rotavirus and norovirus in children with a suspected viral gastroenteritis.

Neonatal jaundice is a risk factor for childhood asthma: a retrospective cohort study.

BACKGROUND: The association between neonatal jaundice and childhood asthma is a new finding of two reports. The purpose of the study was to verify their results. METHODS: Data from 11,321 children were collected from the National Health Insurance Research Database. Their claims data were evaluated from birth to 10 yr old. Children were analyzed as case (those with neonatal jaundice) and controls (those without neonatal jaundice). The diagnostic criteria for asthma were as follows: at least four asthma diagnoses at outpatient services and emergency department (ED), or one asthma diagnosis during an admission. In children fitting the asthma criteria, those with no asthma diagnosis after 1 yr of age were excluded. Mantel-Haenszel's odds ratios were calculated after adjustment for the following confounders: preterm/low birth weight, neonatal infection, other respiratory conditions, other birth conditions, and gender. Asthma rate, onset time, the use of drugs, upper respiratory infection and lower respiratory infection (LRI) rates, hospital admission/ED visit rates, and the effect of phototherapy were evaluated. RESULTS: After adjustment for the confounding factors, the rate of asthma was higher in icteric children (OR: 1.64, 95% CI 1.36-1.98, p < 0.001), and the influence in females was stronger. There still was an association between neonatal jaundice and late onset asthma (asthma onset after 3 yr of age). In asthmatic children, those with neonatal jaundice have increased asthma onset rate before age 6, increased use of inhalant steroids, LRI rates, and ED visits for respiratory disease. CONCLUSIONS: Neonatal jaundice increased the rate and severity of childhood asthma in subjects aged up to 10 yr and may be a risk factor for childhood asthma.

A 12-year-old boy with an infected ectopic ureter presenting with acute appendicitis-like symptoms and acute scrotum.

An ectopic ureter draining into the seminal vesicle or vas deferens in males is a very rare anomaly and is usually associated with renal dysplasia or agenesis. An ectopic ureter associated with a dysplastic kidney is not usually a suspected cause during clinical evaluation of children with abdominal pain. This report presents a rare case of an ectopic ureter associated with a dysplastic kidney with an acute infection in a previously healthy 12-year-old boy, demonstrated by magnetic resonance imaging. He presented with abdominal pain that mimicked acute appendicitis-like symptoms which was subsequently complicated by epididymitis manifesting as an acute scrotum. Clinicians should consider including an ectopic ureter in the differential diagnosis of children presenting with acute abdomen.

Sleep deprivation impairs Ca2+ expression in the hippocampus: ionic imaging analysis for cognitive deficiency with TOF-SIMS.

Sleep deprivation causes cognitive dysfunction in which impaired neuronal plasticity in hippocampus may underlie the molecular mechanisms of this deficiency. Considering calcium-mediated NMDA receptor subunit 1 (NMDAR1) and neuronal nitric oxide synthase (nNOS) activation plays an important role in the regulation of neuronal plasticity, the present study is aimed to determine whether total sleep deprivation (TSD) would impair calcium expression, together with injury of the neuronal plasticity in hippocampus. Adult rats subjected to TSD were processed for time-of-flight secondary ion mass spectrometry, NMDAR1 immunohistochemistry, nNOS biochemical assay, cytochrome oxidase histochemistry, and the Morris water maze learning test to detect ionic, neurochemical, bioenergetic as well as behavioral changes of neuronal plasticity, respectively. Results indicated that in normal rats, strong calcium signaling along with intense NMDAR1/nNOS expression were observed in hippocampal regions. Enhanced calcium imaging and neurochemical expressions corresponded well with strong bioenergetic activity and good performance of behavioral testing. However, following TSD, both calcium intensity and NMDAR1/nNOS expressions were significantly decreased. Behavioral testing also showed poor responses after TSD. As proper calcium expression is essential for maintaining hippocampal neuronal plasticity, impaired calcium expression would depress downstream NMDAR1-mediated nNOS activation, which might contribute to the initiation or development of TSD-related cognitive deficiency.

Life-threatening rhabdomyolysis induced by Streptococcus bovis sepsis in a 6-year-old girl presented to the pediatric emergency department.

Streptococcus bovis infection is an uncommon disease during infancy and childhood. Rhabdomyolysis is frequently a complication of a viral infection in children and typically has a benign course. It has rarely been reported as a complication in cases of bacterial infection, especially those caused by S. bovis. We describe a case of life-threatening rhabdomyolysis after a bacterial infection caused by S. bovis sepsis in a previously healthy 6-year-old girl who presented to our pediatric emergency department. She had an unusually high serum creatine kinase value (peak value, 436,449 IU/L), and she was successfully treated with adequate antibiotic treatment and effective renal replacement therapy. This case illustrates that, although uncommon, S. bovis can cause serious infections during childhood. Pediatric emergency physicians should be aware that uncommon organisms may be able to cause severe infections in susceptible children associated with life-threatening rhabdomyolysis.

Bladder agenesis and bilateral ectopic ureters draining into the vagina in a female infant: demonstrated by MR imaging.

Complete agenesis of the bladder and urethra is an extremely rare congenital anomaly and most of these patients are stillborn or die during infancy. We report the case of a 1-month-old female infant with bladder and urethral agenesis who presented with bilateral dilated and tortuous ectopic ureters draining into the vagina diagnosed using MR imaging. Our patient was maintained on antibiotic prophylaxis and she remained well during the 3-year follow-up. MR imaging can be used as a valuable modality for genitourinary abnormalities, particularly in cases of inconclusive ultrasound or retrograde pyelography findings.

Reading Ability in Patients With Tuberous Sclerosis Complex: Results of Chinese Character Reading and Reading Comprehension Tests.

Background: Most tuberous sclerosis complex (TSC) patients have neurological disorders and are at high risk of academic difficulties. Among academic skills, reading ability is the most important academic skill. The study applied the Chinese character fluency test to measure the word recognition and reading comprehension of TSC children to observe whether they have the characteristics of reading disability, as an indicator of the spectrum of reading ability in TSC patients. Methods: The patients were assessed using the Chinese character fluency test and reading comprehension test to explore the differences in reading ability in terms of gender, age, epilepsy history, genotype, and intelligence level. Results: Of the 27 patients, the assessment of reading accuracy showed statistical differences between intellectual level > 80, PR (p = 0.024), and pass numbers (p = 0.018). For the fluency assessment, there was a difference between different intellectual level (p = 0.050). In the reading comprehension test, there was differences for intellectual level in positivity (p = 0.07) and pass numbers (p = 0.06). Conclusion: The Chinese character fluency and reading comprehension test measure the word recognition and reading comprehension and the spectrum of reading ability in TSC patients. All individuals with TSC, especially those with below average of intellectual ability, should be considered for potential academic difficulties.

The role of procalcitonin for acute pyelonephritis and subsequent renal scarring in infants and young children.

PURPOSE: We assessed the usefulness of procalcitonin as a biological marker in diagnosing acute pyelonephritis and for predicting subsequent renal scarring in young children with a first febrile urinary tract infection. MATERIALS AND METHODS: Children 2 years old or younger with a first febrile urinary tract infection were prospectively studied. Renal parenchymal involvement was assessed by (99m)Tc-dimercaptosuccinic acid scan within 5 days of admission and after 6 months. Serum samples from all patients were tested for procalcitonin, C-reactive protein and white blood cell count measurements. RESULTS: The 112 enrolled patients (age range 24 days to 24 months old) were divided into acute pyelonephritis (76) and lower urinary tract infection (36) groups according to the results of (99m)Tc-dimercaptosuccinic acid scans. Median values of procalcitonin, C-reactive protein and white blood cell count at hospitalization were significantly higher in patients with acute pyelonephritis than in those with lower urinary tract infection. The area under receiver operating characteristic curves showed that procalcitonin was superior to C-reactive protein and white blood cell count as a marker for diagnosing acute pyelonephritis. Initial and post-antibiotic treatment procalcitonin values were significantly higher in children with renal scarring than in those without scarring (p <0.001). Procalcitonin values at hospitalization and after treatment were independent predictors of later renal scarring on logistic regression analysis. CONCLUSIONS: Our results indicate the superior diagnostic accuracy of procalcitonin for predicting acute pyelonephritis in children 2 years old or younger. Higher initial and posttreatment procalcitonin values are independent risk factors for later renal scarring.

Melatonin inhibits microglial activation, reduces pro-inflammatory cytokine levels, and rescues hippocampal neurons of adult rats with acute Klebsiella pneumoniae meningitis.

Acute bacterial meningitis caused by Klebsiella pneumoniae (K. pneumoniae) is a major health threat with a high mortality rate and severe neuro-cognitive sequelae. The intense pro-inflammatory cytokine released from calcium-mediated microglial activation plays an important role in eliciting neuronal damage in the hippocampal region. Considering melatonin possesses anti-inflammatory and immuno-modulatory properties, the present study determined whether melatonin can effectively decrease inflammatory responses and prevent hippocampal damage in animals subjected to K. pneumoniae. Adult rats inoculated with K. pneumoniae received a melatonin injection immediately thereafter at doses of 5, 25, 50, or 100 mg/kg. Following 24 h of survival, all experimental animals were processed for time-of-flight secondary ion mass spectrometry (for detecting glial calcium intensity), isolectin-B4 histochemistry (reliable marker for microglial activation), pro-inflammatory cytokine measurement as well as cytochrome oxidase and in situ dUTP end-labeling (representing neuronal bio-energetic status and apoptotic changes, respectively). Results indicate that in K. pneumoniae-infected rats, numerous calcium-enriched microglia, enhanced pro-inflammatory cytokine, and various apoptotic neurons with low bio-energetic activity were detected in hippocampus. Following melatonin administration, however, all parameters including glial calcium intensity, microglial activation, pro-inflammatory cytokine levels, and number of apoptotic neurons were successfully decreased with maximal change observed at a melatonin dose of 100 mg/kg. Enzymatic data corresponded well with above findings in which all surviving neurons displayed high bio-energetic activity. As effectively reducing glia-mediated inflammatory response is neuro-protective to hippocampal neurons, the present study supports the clinical use of melatonin as a potential therapeutic agent to counteract K. pneumoniae meningitis-induced neuro-cognitive damage.