en Infectious Diseases Infectious Diseases Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:14pt"><span new="" roman="" times=""><b><i><span style="color:blue">Background</span></i></b><i><span style="color:blue">:</span></i> <span style="color:black">Post-neurosurgical meningitis is a significant cause of mortality and morbidity. In this study we aimed to compare the differences of clinical, laboratory features and outcomes between the post-neurosurgical meningitis caused by gram-negative bacilli (GNB) and gram-positive cocci (GPC).</span><span style="font-size:9.0pt"></span></span></span><br> <span style="line-height:14pt"><span new="" roman="" times=""><b><i><span style="color:blue">Methods:</span></i></b> <span style="color:black">Cases of post-neurosurgical meningitis (with positive CSF culture) were included. After classifying patients as GNB and GPC groups, clinical and paraclinical data were compared.</span><i><span style="font-size:9.0pt"></span></i></span></span><br> <span style="line-height:14pt"><span new="" roman="" times=""><b><i><span style="color:blue">Results:</span></i></b> <span style="color:black">Out of 2667 neurosurgical patients, CSF culture was positive in 45 patients. 25 (54.3%) were GNB, 19 (41.3%) GPC. The most common microorganisms were <i>Klebsiella pneumoniae</i> (n=14, 31.1%),<i> Coagulase negative staphylococcus</i> (n=8, 17.8%), <i>Staphylococcus aureus</i> (n=6, 13.3%), <i>Acinetobacter baumannii</i> (n=4, 8.9%), <i>Pseudomonas aeruginosa</i> (n=2, 4.4%), and <i>Escherichia coli</i> (n=2, 4.4%). There were no correlation between CSF Leakage, Surgical site appearance, presence of drain, Age and GCS between two groups (<i>P</i>=0.11, <i>P</i>=0.28, <i>P</i>=0.06,<i> P</i>=0.86, <i>P</i>=0.11 respectively). The only different laboratory indexes were ESR (86.8 mm/h vs. 59.5 mm/h, <i>P</i>=0.01) and PCT (13.1 ng/ml vs. 0.8 ng/ml, <i>P</i>=0.02) which were higher in GNB cases. 20% (n=5) of patients with GNB meningitis received preoperative corticosteroid, while none of GPC cases received (<i>P</i>=0.03). The median length of hospitalization for GNB and GPC cases was 56 and 44.4 days respectively (<i>P</i>=0.3).</span><b><i><span style="color:blue"></span></i></b></span></span><br> <span style="line-height:14pt"><span new="" roman="" times=""><b><i><span style="color:blue">Conclusion</span></i></b><i><span style="color:blue">:</span></i> <span style="color:black">The GNB antibiotic coverage should be designed more carefully in post-neurosurgical meningitis especially in patients with recent corticosteroid therapy and elevated ESR and procalcitonin.</span></span></span></span></span><span style="font-size:12pt"><span style="line-height:14pt"><span new="" roman="" style="font-family:" times=""><b><i><span style="font-size:10.0pt"><span style="color:#0033cc"></span></span></i></b></span></span></span> Nosocomial Infections, Neurosurgery, Meningitis, Gram negative bacilli 469 474 http://caspjim.com/browse.php?a_code=A-10-1276-4&slc_lang=en&sid=1 Mehdi Zeinalizadeh m.zeinalizade@gmail.com 100319475328460037503 100319475328460037503 No Department of Neurosurgery, Brain and Spinal Cord Injury Research Center, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran Roya Yazdani md.yazdani21@gmail.com 100319475328460037504 100319475328460037504 No Department of Neurology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Mohammad Mehdi Feizabadi mfeizabadi@tums.ac.ir 100319475328460037505 100319475328460037505 No Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Maryam Shadkam shadkamm8@gmail.com 100319475328460037506 100319475328460037506 No Department of Microbiology, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran Arash Seifi a-seifi@sina.tums.ac.ir 100319475328460037507 100319475328460037507 No Department of Infectious Diseases, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran Seyed Ali Dehghan Manshadi sealdema@yahoo.com 100319475328460037508 100319475328460037508 No Department of Infectious Diseases, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran Alireza Abdollahi alireza.a1345@yahoo.com 100319475328460037509 100319475328460037509 No Department of Pathology, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran Mohammadreza Salehi salehi.mohamad3@gmail.com 100319475328460037510 100319475328460037510 Yes Department of Infectious Diseases, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran