How long should cerebrospinal fluid cultures be held to detect shunt infections?

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>Infections of CSF hardware may be indolent, and some patients have received antibiotic treatment for various reasons before CSF is obtained to check for a shunt infection. At present, there are few data in the literature to guide the decision as to how long to hold CSF specimens when attempting to diagnose hardware infections, and institutions vary in the duration at which cultures are considered “final.”</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>The authors reviewed the microbiology data from CSF specimens obtained from shunts, ventriculostomies, reservoirs, and lumbar drains at their institution over a 36-month period to discover how long after collection cultures became positive. The authors also sought to discover whether this time was affected by prior treatment with antibiotics.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Of 158 positive CSF specimens obtained from hardware, the time to recovery ranged between 1–10 days, with a mean of 3.02 days (SD 2.37 days, 95% CI 2.66–3.38 days). One hundred and twenty-seven positive specimens were associated with clinical infections, and ~ 25% of these grew organisms after &gt; 3 days, with some as long as 10 days after specimens were obtained. The most common organisms grown from individual patients were coagulase-negative <jats:italic>Staphylococcus</jats:italic> spp (34 cultures), <jats:italic>Propionibacterium</jats:italic> spp (21), <jats:italic>Bacillus</jats:italic> spp (6), <jats:italic>Pseudomonas aeruginosa</jats:italic> (4), and <jats:italic>Staphylococcus aureus</jats:italic> (4 cultures). Mean and maximum days to recovery were different across species, with <jats:italic>S. aureus</jats:italic> showing the shortest and <jats:italic>Propionibacterium</jats:italic> spp showing the longest incubation times. There appeared to be no significant difference in the time to recovery between specimens obtained in patients who had received prior antibiotic treatment versus those who had not.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>A substantial number of positive CSF specimens obtained in patients with clinical infections grew bacteria after &gt; 3 days, with some requiring as long as 10 days. Thus, a routine 10-day observation period for CSF specimens can be justified.</jats:p></jats:sec>

Raised Proinflammatory Cytokine Production Within Cerebrospinal Fluid Precedes Fever Onset in Patients With Neurosurgery-Associated Bacterial Meningitis*

“…However, because bacterial meningitis has the potential to cause substantial neurological deficits, empirical antibiotic treatment is often given before CSF collection, thereby reducing its diagnostic value. Furthermore, it takes approximately 3 days for routine CSF cultures to yield results, limiting its clinical use acutely (39). Of note, fever is frequently described as a significant clinical feature of bacterial meningitis (5).…”

Diagnostic Approach to Health Care- and Device-Associated Central Nervous System Infections

“…Prior antibiotic treatment is a common cause of falsely negative CSF Gram stain and culture, with up to 50% of patients having received antibiotics before CSF collection in some studies (21). Interlaboratory differences in the set up and processing of devicecollected CSF samples are another major cause of variable culture yield and performance across institutions (13,33,(42)(43)(44)(45). The recommendations regarding the need for CSF centrifugation prior to culture, anaerobic culture, anaerobic transport media, broth culture, duration of broth incubation, and the role, appropriateness, and procedure for CNS device tip cultures are frequently not explicit and differ between standard clinical microbiology references (44,45).…”

“…Several studies have reported an increase in the proportion of positive CSF cultures and clinically significant Propionibacterium spp. infections with the addition of anaerobic culture (solid media or broth) and prolonged incubation of broth media (10 to 14 days) (13,30,42,46). Calderaro et al observed a shorter time-to-positivity and a 79% increase in the detection of aerobic bacteria and yeast with an inoculation of 1 to 3 ml CSF into a Bactec Peds Plus/F blood culture bottle over that with conventional agar culture (43).…”

Cerebrospinal Fluid Shunt Infections

“…ve Acinetobacter spp. gibi non-fermentatif bakteriler, daha az sıklıkta olmakla birlikte, etken profi li içerisindedirler (22). Etyolojide yer alabilen bu Gram-negatif çomakların, distal ucu peritonda biten şant tiplerinde daha ön planda infeksiyon etkeni olması beklenir.…”