Progression of cerebrospinal fluid cell count and differential over a treatment course of shunt infection

Object The physiological reaction of CSF white blood cells (WBCs) over the course of treating a shunt infection is undefined. The authors speculated that the CSF WBC count varies with different infecting organisms in peak level and differential percentage of polymorphonuclear (PMN) leukocytes, lymphocytes, monocytes, and eosinophils. The authors hope to identify clinically useful trends in the progression of CSF WBCs by analyzing a large group of patients with successfully treated shunt infections. Methods The authors reviewed 105 successfully treated cases of shunt infections at Riley Hospital for Children. The study dates ranged from 2000 to 2004; this represented a period prior to the routine use of antibiotic-impregnated shunt catheters. They analyzed the following organisms: coagulase-negative staphylococci, Staphylococcus aureus, Propionibacterium acnes, Streptococcal species, and gram-negative organisms. The initial CSF sample at diagnosis was analyzed, as were levels over 14 days of treatment. Model fitting was performed to generate curves for the expected progression of the WBC counts and the differential PMN leukocytes, lymphocyte, monocyte, and eosinophil percentages. Results Gram-negative organisms resulted in a higher initial (p = 0.03) and peak WBC count with a greater differential of PMN leukocytes compared with other organisms. Propionibacterium acnes infections were associated with a significantly lower WBC count and PMN leukocytes percentage (p = 0.02) and higher eosinophil percentage (p = 0.002) than other organisms. The pattern progression of the CSF WBC count and differential percentages was consistent for all infections. There was an initial predominance of PMN leukocytes, followed by a delayed peak of lymphocytes, monocytes, and eosinophils over a 14-day course. All values trended toward zero over the treatment course. Conclusions The initial and peak levels of CSF WBCs vary with the infecting organisms. The CSF cell counts showed a predictable pattern during the treatment of shunt infection. These trends may be useful to the physician in clinical decision making, although there is a wide range of variability.

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Origin of Organisms Infecting Ventricular Shunts

Neurosurgery ◽

10.1227/00006123-198805000-00009 ◽

1988 ◽

Vol 22 (5) ◽

pp. 868-872 ◽

Cited By ~ 57

Author(s):

Scott Shapiro ◽

Joel Boaz ◽

Martin Kleiman ◽

John Kalsbeck ◽

John Mealey

Keyword(s):

Staphylococcus Aureus ◽

Pediatric Population ◽

Antibiotic Sensitivity ◽

Shunt Infection ◽

Gram Negative ◽

Skin Bacteria ◽

Sensitivity Data ◽

Time Of Operation ◽

Shunt Infections ◽

Infecting Organisms

Abstract Results of skin cultures obtained before 413 of 505 operations for cerebrospinal fluid-diverting ventricular shunt placement or revision in a pediatric population from April 1980 to May 1983 are analyzed and compared to results of cultures from 20 subsequent shunt infections. Sensitivities to 11 different antibiotics were determined for each isolate cultured. The total operative infection rate was 20 of 505 (4%). Gram-negative bacilli alone accounted for 3 of 20 (15%) shunt infections. One gram-negative bacillus/Staphylococcus aureus infection occurred. Factors predisposing for gramnegative bacillus shunt infection were found in all 4 cases. The majority of shunt infections were caused by typical resident skin organisms: Staphylococcus epidermidis alone, 9/20 (45%); Staphylococcus aureus alone, 4/20 (20%); Corynebacterium sp., 1/20 (5%); α-Streptococcus with S. epidermidis, 1/20 (5%); and Micrococcus with S. epidermidis, 1/20 (5%). Only 4 (20%) of the 20 shunt infections were due to organisms identical to those originally grown from the skin. Another 4 (20%) seemed to be infected with a strain of organism different from that initially recovered from the skin. The remaining skin organism shunt infections may or may not have come from the patient's skin. The data suggest that not all skin organism shunt infections arise from contamination by resident skin bacteria at the incision sites at the time of operation. Alternate sources for the infecting organisms are discussed. The antibiotic sensitivity data on skin isolates and shunt isolates suggest that vancomycin is the antibiotic best suited for prophylaxis against shunt infection at our institution.

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Gram-Negative Diabetic Foot Osteomyelitis

The International Journal of Lower Extremity Wounds ◽

10.1177/1534734613477423 ◽

2013 ◽

Vol 12 (1) ◽

pp. 63-68 ◽

Cited By ~ 17

Author(s):

Javier Aragón-Sánchez ◽

Benjamin A. Lipsky ◽

Jose L. Lázaro-Martínez

Keyword(s):

Blood Cell ◽

Glycated Hemoglobin ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Cell Counts ◽

Blood Cell Counts ◽

White Blood Cell Counts ◽

Gram Negative Organisms ◽

Diabetic Foot Osteomyelitis

Osteomyelitis frequently complicates infections in the feet of patients with diabetes. Gram-positive cocci, especially Staphylococcus aureus, are the most commonly isolated pathogens, but gram-negative bacteria also cause some cases of diabetic foot osteomyelitis (DFO). These gram-negatives require different antibiotic regimens than those commonly directed at gram-positives. There are, however, few data on factors related to their presence and how they influence the clinical picture. We conducted a retrospective study to determine the variables associated with the isolation of gram-negative bacteria from bone samples in cases of DFO and the clinical presentation of these infections. Among 341 cases of DFO, 150 had a gram-negative isolate (alone or combined with a gram-positive isolate) comprising 44.0% of all patients and 50.8% of those with a positive bone culture. Compared with gram-positive infections, wounds with gram-negative organisms more often had a fetid odor, necrotic tissue, signs of soft tissue infection accompanying osteomyelitis, and clinically severe infection. By multivariate analysis, the predictive variables related to an increased likelihood of isolating gram-negatives from bone samples were glycated hemoglobin <7% (odds ratio [OR] = 2.0, 95% confidence interval [CI] = 1.1-3.5) and a wound caused by traumatic injury (OR = 2.0, 95% CI = 1.0-3.9). Overall, patients whose bone samples contained gram-negatives had a statistically significantly higher prevalence of leukocytosis and higher white blood cell counts than those without gram-negatives. In conclusion, gram-negative organisms were isolated in nearly half of our cases of DFO and were associated with more severe infections, higher white blood cell counts, lower glycated hemoglobin levels, and wounds of traumatic etiology.

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Cerebrospinal fluid ascites complicating ventriculoperitoneal shunting

Journal of Neurosurgery ◽

10.3171/jns.1984.61.1.0180 ◽

1984 ◽

Vol 61 (1) ◽

pp. 180-183 ◽

Cited By ~ 22

Author(s):

Robert A. Yount ◽

Mark C. Glazier ◽

John Mealey ◽

John E. Kalsbeck

Keyword(s):

Cerebrospinal Fluid ◽

Blood Cell ◽

Surgical Intervention ◽

Shunt Infection ◽

Content Type ◽

Protein Levels ◽

Ventriculoperitoneal Shunting ◽

Wbc Count ◽

Shunt Infections ◽

Fine Print

✓ Four cases of cerebrospinal fluid (CSF) ascites secondary to ventriculoperitoneal shunting are described. It is possible to differentiate CSF ascites from a CSF-filled pseudocyst by the characteristic bowel gas pattern on films of the abdomen and by the presence of shifting dullness. Two of the patients had active shunt infections, and had ascitic fluid with a protein level greater than 3 gm% and a white blood cell (WBC) count greater than 1000/cu mm. Both were treated successfully with antibiotics and removal of the shunt from the peritoneum. Two other patients had no evidence of infection, protein levels of less than 2 gm%, and WBC count less than 100 cu mm. These disorders resolved spontaneously. A review of 18 cases reported in the literature shows thatthe etiology of CSF ascites in the absence of shunt infection is multifactorial, and no features are consistently present in all cases. Ascites without infection may resolve spontaneously without surgical intervention.

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In Vivo Efficacy of 1- and 2-Gram Human Simulated Prolonged Infusions of Doripenem against Pseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00282-09 ◽

2009 ◽

Vol 53 (10) ◽

pp. 4352-4356 ◽

Cited By ~ 21

Author(s):

Jared L. Crandon ◽

Catharine C. Bulik ◽

David P. Nicolau

Keyword(s):

Pseudomonas Aeruginosa ◽

Animal Studies ◽

Multidrug Resistant ◽

Free Time ◽

In Vivo Efficacy ◽

Gram Negative ◽

Wide Range ◽

Gram Negative Organisms

ABSTRACT Doripenem is a new carbapenem antimicrobial with activity against a range of gram-negative organisms, including Pseudomonas aeruginosa. Previous animal studies have shown efficacy of a 500-mg dose of doripenem given as a 4-h infusion against P. aeruginosa with MICs of ≤4 μg/ml. The purpose of this study is to evaluate the efficacy of 1- and 2-g-dose prolonged infusions of doripenem against a wide range of P. aeruginosa isolates in the neutropenic murine thigh model. Eighteen clinical P. aeruginosa isolates (MIC range, 2 to 32 μg/ml) were used; 15 of these were multidrug resistant. After infection, groups of mice were administered doripenem doses designed to simulate the free time above the MIC (fT>MIC) observed in humans given 1 or 2 g of doripenem every 8 h as a 4-h infusion. Efficacy correlated well with published fT>MIC bactericidal targets of 40%. After 24 h, 1- and 2-g doses achieved approximately ≥2 log decreases in CFU against isolates with MICs of ≤8 and 16 μg/ml, respectively (fT>MIC range, 52.5 to 95%). Results with organisms with higher MICs, where fT>MIC was 0%, were variable, including both increases and decreases in CFU. Compared with 1-g doses, statistically greater efficacy was noted for 2-g doses against three of the eight isolates with MICs of ≥16 μg/ml. While MIC distributions of P. aeruginosa at present necessitate increased exposures for only the most-resistant isolates, the ability of increased doses to achieve pharmacodynamic targets and the efficacy observed when these targets were attained could prove useful when these resistant isolates are encountered.

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In Vivo Efficacy of Simulated Human Dosing Regimens of Prolonged-Infusion Doripenem against Carbapenemase- Producing Klebsiella pneumoniae

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00026-10 ◽

2010 ◽

Vol 54 (10) ◽

pp. 4112-4115 ◽

Cited By ~ 42

Author(s):

Catharine C. Bulik ◽

David P. Nicolau

Keyword(s):

Klebsiella Pneumoniae ◽

White Blood Cells ◽

Multidrug Resistant ◽

Gram Negative ◽

Wide Range ◽

Dosing Regimens ◽

Gram Negative Organisms ◽

Immunocompromised Mice

ABSTRACT Carbapenemase-producing Klebsiella pneumoniae (KPC) bacteria are rapidly becoming one of the most detrimental drug-resistant Gram-negative pathogens. Doripenem is the newest FDA-approved carbapenem that has the greatest in vitro potency against a wide range of Gram-negative organisms, including multidrug-resistant organisms. Previous work in an animal model has shown efficacy against Pseudomonas aeruginosa with MICs above the current breakpoints of susceptibility. The purpose of this study is to evaluate the efficacy of 1-g and 2-g dose prolonged infusions of doripenem against KPC isolates in both an immunocompetent and neutropenic murine thigh model. Seven clinical KPC isolates (broth microdilution [BMD] MIC range, 4 to 32 μg/ml; Etest MIC range, 3 to >32 μg/ml) were used. After infection, groups of mice were administered doripenem doses previously shown to simulate the exposures observed in humans after the administration of 1 or 2 g every 8 h as a 4-h infusion. In immunocompromised mice, 1- and 2-g doses of doripenem achieved bacteriostasis against isolates with MICs up to and including 8 μg/ml and 16 μg/ml, respectively. In immunocompetent animals, statistically significant reductions in the number of CFU were observed with overall decreases of approximately 1 log (P < 0.05). While carbapenemase-producing Klebsiella pneumoniae continues to decrease our meager supply of active agents, the ability of doripenem to produce CFU reductions in the presence of white blood cells (WBCs) using humanized exposures suggests the potential utility of this agent in combination against this increasingly problematic pathogen.

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The intestinal flora of colonization-resistant mice

Journal of Hygiene ◽

10.1017/s0022172400021665 ◽

1971 ◽

Vol 69 (3) ◽

pp. 413-421 ◽

Cited By ~ 45

Author(s):

F. Wensinck ◽

J. G. H. Ruseler-van Embden

Keyword(s):

Escherichia Coli ◽

Yeast Extract ◽

Propionibacterium Acnes ◽

Intestinal Flora ◽

Ammonium Phosphate ◽

Anaerobic Conditions ◽

Gram Negative ◽

Gram Negative Organisms

SUMMARYTo facilitate the isolation of anaerobes from cultures in which swarming organisms were present Roux flasks were adapted to provide anaerobic conditions. Using these flasks, five species of anaerobes were isolated from the caecum of mice resistant to colonization withEscherichia coliand other Gram-negative organisms. These species accounted for the majority of organisms seen in films of caecal material. No aerobes were isolated and the flora of these mice apparently consisted of a limited number of anaerobes representing part of the intestinal flora of conventional mice. Three of the species were clostridia and another was identified asPropionibacterium acnes. One species resembledCatenabacteriumbut was not identified. One of theClostridiumspecies could only be isolated when the medium was supplemented with yeast extract and vitamins. This species sporulated on media with ammonium phosphate as the source of nitrogen; tryptone completely suppressed sporulation.

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Effect of introduction of antibiotic-impregnated shunt catheters on cerebrospinal fluid shunt infection in children: a large single-center retrospective study

Journal of Neurosurgery Pediatrics ◽

10.3171/2013.10.peds13189 ◽

2014 ◽

Vol 13 (1) ◽

pp. 101-106 ◽

Cited By ~ 14

Author(s):

Greg James ◽

John C. Hartley ◽

Robert D. Morgan ◽

Jessica Ternier

Keyword(s):

Staphylococcus Aureus ◽

Shunt Infection ◽

Control Group ◽

Coagulase Negative Staphylococcus ◽

Study Group ◽

Infection Rates ◽

Gram Negative ◽

Enterococcus Spp ◽

Historical Group ◽

Gram Negative Organisms

Object Infection after both primary and revision shunt surgeries remains a major problem in pediatric neurosurgical practice. Antibiotic-impregnated shunt (AIS) tubing has been proposed to reduce infection rates. The authors report their experience with AIS catheters in their large pediatric neurosurgery department. Methods The authors conducted a retrospective case review of consecutive shunt operations performed before (1993–2003) and after (2005–2009) introduction of AIS tubing, with analysis of shunt infection rates and causative organisms identified. Results The historical control group consisted of 1592 consecutive shunt operations (657 primary insertions), and the AIS study group consisted of 500 consecutive shunt operations (184 primary insertions). Patients ranged in age from 0–17 years. In the historical group, 135 infections were identified (8.4%). In the AIS study group, 25 infections were identified (5%), representing a significant reduction (p < 0.005). The latency to diagnosis of infection was 23 days in the historical group and 139 days in the AIS study group. The infection rates in infants 0–6 months of age were 12.2% (historical group) and 6.7% (AIS group, p < 0.005), and in infants 7–12 months of age the rates were 7.9% (historical group) and 2.7% (AIS group, p < 0.005). In the historical control group, the frequency rank order of causative organisms was coagulase-negative staphylococcus (51.9%), Staphylococcus aureus (31.6%), streptococcus or enterococcus spp. (8.8%), gram-negative organisms (4.4%), and Propionibacterium acnes (2.2%). Organisms responsible for infections in AIS were S. aureus (40%), followed by streptococcus or enterococcus spp. (20%), P. acnes and coagulase-negative staphylococcus (both 16%), and gram-negative organisms (4%). No unusually antibiotic-resistant bacteria were identified in either group. The authors further subdivided the AIS group into those undergoing primary AIS insertion (Subgroup 1), those undergoing revision of non-AIS systems using AIS components (Subgroup 2), and those undergoing revision of AIS systems using AIS components (Subgroup 3). Infection rates were 1.6% in Subgroup 1, 2.5% in Subgroup 2, and 11.7% in Subgroup 3. Staphylococcus aureus was the most common organism identified in infections of the Subgroups 2 and 3. Conclusions Use of AIS tubing significantly improves shunt infection rates in both general pediatric and infant populations with no evidence of increased antibiotic resistance, which is in agreement with previous studies. However, the increased infection rate in revision surgery in children with AIS catheters in situ raises questions about their long-term application.

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Relationship of causative organism and time to infection among children with cerebrospinal fluid shunt infection

Journal of Neurosurgery Pediatrics ◽

10.3171/2019.2.peds18638 ◽

2019 ◽

Vol 24 (1) ◽

pp. 22-28

Author(s):

Matthew R. Test ◽

Kathryn B. Whitlock ◽

Marcie Langley ◽

Jay Riva-Cambrin ◽

John R. W. Kestle ◽

...

Keyword(s):

Cerebrospinal Fluid ◽

Tertiary Care ◽

Predictor Variable ◽

Shunt Infection ◽

Csf Shunt ◽

Causative Organism ◽

Gram Negative ◽

Significant Difference ◽

Csf Shunt Infection ◽

Gram Negative Organisms

OBJECTIVEInfection is a common complication of cerebrospinal fluid (CSF) shunts, occurring in 6%–20% of children. Although studies are limited, Staphylococcus aureus is thought to cause more rapid and aggressive infection than coagulase-negative Staphylococcus (CONS) or gram-negative organisms. The authors’ objective was to evaluate the relationship between the causative organisms of CSF shunt infection and the timing of infection.METHODSThe authors performed a retrospective cohort study of children who underwent CSF shunt placement at a tertiary care children’s hospital over a 9-year period and subsequently developed a CSF shunt infection. The primary predictor variable was the causative organism recovered from CSF culture, characterized as S. aureus, CONS, or gram-negative organisms. The primary outcome was time to infection, defined as the number of days from most recent shunt intervention to the diagnosis of the infection. The association between causative organism and time to infection was visualized using Kaplan-Meier curves, and statistical comparisons were made using nonparametric Kruskal-Wallis tests.RESULTSAmong 103 children in whom a CSF shunt infection developed, the causative organism was CONS in 57 (55%), S. aureus in 19 (18%), and gram-negative organisms in 9 (9%). The median time to infection did not differ (p = 0.81) for infections caused by CONS (20 days, IQR 11–40), S. aureus (26 days, IQR 12–95), and gram-negative organisms (23 days, IQR 17–34).CONCLUSIONSNo significant difference in time to infection based on the causative organism was observed among children with a CSF shunt infection.

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