Blood Agar Culture Research Articles

Confocal Microscopy for Nocardia Keratitis

To assess the role of confocal microscopy for in vivo detection of Nocardia in patients with microbial keratitis. Retrospective interventional case series. Three patients with microbiologically proven Nocardia keratitis. Confocal microscopy. We performed confocal microscopy in microbiologically proven cases of Nocardia asteroides keratitis. A masked observer examined the images. For better understanding of the images, we also performed confocal microscopy on a blood agar culture plate with Nocardia growth. Confocal microscopy of infiltrated cornea revealed highly reflective, short, thin branching filaments with bright inflammatory cells in the background. The filaments were seen clearly at the edge of the infiltrate. In scans with faint images, these filaments became more visible on inversion of bright and dark components. Confocal microscopy of cultured organisms also revealed filamentous beaded structures with a morphology identical to that of those seen in vivo. Nocardia, a filamentous bacterium, produces a distinct image on confocal microscopy. This in vivo examination technique may be useful in cases of deep-seated infiltrates where routine microbiology workup does not yield positive results.

Trypanosomatidae de importancia en salud pública en animales silvestres y sinantrópicos en un area rural del municipio Tovar del estado Mérida, Venezuela.

Chagas disease and leishmaniasis are important public health problems due to their high frequency and broad distribution in Latin America. Understanding of the roles of reservoir animals is crucial for a global assessment of the epidemiology of these diseases. To identify parasites classed as Trypanosomatidae as they occurred in sylvatic animals, and to establish rates of coinfection. Sylvatic animals were systematically captured in the rural area of El Carrizal, Merida State, Venezuela, betweenJuly, 1998 and February, 2000. The captures were made in Tomahawk type homemade traps, placed 15 nights per month throughout the study period. Blood was extracted from each captured and anesthetized animal by means of cardiac puncture. The search for trypanosomatids was undertaken by fresh blood examination, Giemsa stained blood smears and by means of blood-agar culture. Occasional xenodiagnoses were made to check diagnostic accuracy. The isolates obtained in culture media were identified by restriction fragment analysis and hybridization with specific probes. Three species of sylvatic animals (n = 215) were captured: Rattus spp. (135), Sigmodon hispidus (73) and Didelphis marsupialis (7). From them, three species of Trypanosomatidae were identified: Leishmania (Viannia) guyanensis, Trypanosoma cruzi and Trypanosoma lewisi. Trypanosoma. cruzi was identified in D. marsupialis (4/7), S. hispidus (1/73) and Rattus spp. (1/ 135), whereas L. (V.) guyanensis and T. lewisi were identified only in Rattus spp., 1/135 and 12/ 135, respectively. The coexistence of these genetically related hemoflagellates in sylvatic hosts was important for understanding the immunological interactions that may be established in reservoir animals, and the possible implications that this may have for the susceptible host. Finally, the identification of L. (V.) guyanensis in Rattus spp and T. cruzi in S. hispidus constituted the first reports of this relationship in Venezuela.

Looks Like Cat-Scratch Disease, but. . .

Many disease processes cause lymph-node enlargement. To investigate the bacterial causes, investigators at a national reference center in France that receives lymph-node specimens from patients with suspected cat-scratch disease (CSD) analyzed 786 specimens collected from January 2001 through August 2005. They performed blood agar and cell culture and molecular testing (PCR for the 16S rDNA gene and …

Production and Validation of the Use of Gamma Phage for Identification of Bacillus anthracis

Gamma phage specifically lyses vegetative cells of Bacillus anthracis and serves as part of the basis for identification of isolates from agar cultures. We report our study to standardize gamma phage production and preparation and to validate the assay for routine use. Unstable phage preparations were largely reduced through propagation of phage on blood agar cultures of the avirulent B. anthracis strain CDC684 and were adequately stable for extended storage beyond 1 to 2 years at 4 degrees C, provided that the preparation initially gave rise to clearly discernible plaques (macroplaques, 5 to 10 mm in diameter) on dilution at 1:8 or greater during potency testing with the Sterne strain or its equivalent. The primary intent of the assay was to test nonhemolytic, ground-glass-appearing bacterial B. anthracis-like colonies arising from culture of clinical or nonclinical samples on 5% sheep blood agar. Specifically, the assay was designed to show clear or primarily clear circular zones of lysis on bacterial lawns at the site of gamma phage inoculation after incubation at 35 degrees C +/- 2 degrees C for 20 h. When tested with 51 B. anthracis strains and 49 similar non-B. anthracis Bacillus species, the analytical specificity was >95%, a value that is intentionally low because our study design included two rare nonsusceptible B. anthracis strains as well as a rare susceptible non-B. anthracis strain, B. cereus ATCC 4342. Repeatability, day-to-day precision, and analyst-to-analyst precision were superior. The assay was rugged to variations among phage lots, phage concentration, amounts of bacterial inoculum, and incubation times as short as 6 to 8 h. System suitability evaluation showed improved robustness when bacterial lawns were tested with high- and low-density inoculum using the first and second quadrants of a serial four-quadrant streak on 5% sheep blood agar plates.

Specimen storage in transport medium and detection of group B streptococci by culture.

Recovery of group B streptococci (GBS) was assessed in 1,204 vaginorectal swabs stored in Amies transport medium at 4 or 21 degrees C for 1 to 4 days either by direct inoculation onto Granada agar (GA) or by culture in blood agar (BA) and GA after a selective broth enrichment (SBE) step. Following storage at 4 degrees C, GBS detection in GA was not affected after 72 h by either direct inoculation or SBE; however, GBS were not detected after SBE in the BA subculture in some samples after 48 h of storage and in GA after 96 h. After storage at 21 degrees C, loss of GBS-positive results was significant after 48 h by direct inoculation in GA and after 96 h by SBE and BA subculture; some GBS-positive samples were not detected after 24 h of storage followed by SBE and BA subculture or after 48 h of storage followed by SBE and GA subculture. Storage of swabs in transport medium, even at 4 degrees C, produced after 24 h an underestimation of the intensity of GBS colonization in most specimens. These data indicate that viability of GBS is not fully preserved by storage of vaginorectal swabs in Amies transport medium, mainly if they are not stored under refrigeration.

Would a Titanium Dioxide Air Cleaner Reduce Colony-Forming Units in Standard Air Ventilation ORs?

INTRODUCTION: Operating room air ventilation standards have been established to reduce the likelihood of contracting a surgical site infection (SSI) related to OR air ventilation. A question remains, however, regarding whether newer technology can further reduce the number of circulating airborne contaminants. From September through December 2002, air sampling was performed that compared standard air ventilation and titanium dioxide air filters during cardiovascular surgery at a 360-bed medical center in northwestern Pennsylvania. METHODS: On four separate days in one operating room, microbiological air tests were conducted to determine viable airborne bacterial counts, expressed as colony-forming units per cubic meter of air (CFU/m3). This was accomplished using an N-6 single stage air sampler with an Andersen high-volume air pump calibrated at 28.3 liters per minute. Air was sampled during 3-minute cycles at eight specific locations with the samples deposited on Remel Sheep Blood Agar (SBA) culture plates. Samples were taken at baseline (standard ventilation) and with the titanium filters turned on. RESULTS: For the eight sites in the operating room, an overall ANOVA revealed a significant difference in mean counts for the four sampling times (p=0.0014). Multiple comparison tests revealed that baseline standard air ventilation CFU/m3 values were consistently greater than the titanium dioxide filtered operational tests (p <0.0075). CONCLUSION: The use of titanium filters significantly reduced airborne contamination in the operating room. The fact that the baseline values were nearly identical with the filters off, indicated that good control existed and conditions were similar for each test.

Would a Titanium Dioxide Air Cleaner Reduce the Colony-Forming Unit Counts in Laminar Air Flow ORs?

INTRODUCTION: A previous study determined that titanium oxide filters added to standard air ventilation reduced the colony-forming units per cubic meter (CFU/m3) in the operating room. Laminar Air Flow has been shown to dramatically reduce CFU/m3 in various studies, however, its use depends on room size, configuration, and ventilation requirements to allow for maximum efficiency. From March through May 2003, air sampling was done to determine the performance of titanium dioxide filters as compared to Laminar Air Flow during orthopedic surgery in a 360-bed medical center in northwestern Pennsylvania. METHODS: In one operating suite, the Laminar Air Flow, titanium dioxide filters, and standard air flow were tested on separate days using microbiological air tests to determine viable airborne bacterial counts. Samples were obtained using an N-6 single stage air sampler with an Andersen high-volume air pump calibrated at 28.3 liters per minute and bacterial growth was expressed as colony-forming units (CFUs) per cubic meter of air (CFU/m3). The air samples collected at eight specific locations were allowed to run for 3-minute cycles and the potential contaminants deposited on Remel Sheep Blood Agar (SBA) culture plates. RESULTS: Using a Friedman Test, the Laminar Air Flow results showed a significant bacterial reduction (p<0.014) in mean counts for the three sampling times as compared to the titanium dioxide filters for the eight sites in the operating room, CONCLUSION: Laminar Air Flow significantly reduced CFUs per cubic meter compared to titanium dioxide filters.

Temporal association of the appearance of mucoid strains of Streptococcus pyogenes with a continuing high incidence of rheumatic fever in Utah.

Our objective was to confirm an observed temporal association of increased numbers of rheumatic fever cases concomitant with the appearance of an increased prevalence of mucoid strains of Streptococcus pyogenes. During the resurgence of rheumatic fever (RF) that has occurred in the Intermountain area surrounding Salt Lake City, Utah, since 1985, the largest number of cases occurred in 1985 and 1986 and 12 years later in 1997 and 1998. During the initial outbreak and the later exacerbation of the resurgence, an increased number of mucoid strains of S pyogenes were present in the community. The referred cases of RF that fulfilled Jones criteria have been systematically reviewed by the medical staff at Primary Children's Medical Center yearly since 1985. Before the resurgence of RF, a program was initiated by the microbiology laboratory at Primary Children's Medical Center to store frozen isolates of S pyogenes. All frozen specimens were randomly selected and entered into a log; the coded entry allowed for comments regarding the origin of the isolate and whether the isolate had a mucoid appearance on the blood agar culture plate. This log was reviewed in October 2002 to determine whether the percentage of frozen mucoid isolates stored during the resurgence of RF would support the clinical and epidemiologic suspicion that mucoid isolates seemed to be present with a higher frequency during the 2 periods of high incidence of RF. The percentage of mucoid isolates was compared with the yearly number of cases of RF. A Pearson r correlation analysis was completed to determine whether there was a significant association between the percentage of mucoid isolates and the number of cases of RF. The highest number of cases of RF was temporally associated with the highest percentage of mucoid isolates. There was statistically significant correlation between percentage of mucoid strains and the number of RF cases. The Utah experience with the resurgence of RF in a civilian population during the last decade and a half of the 20th century confirmed the temporal association of mucoid strains of S pyogenes, primarily M-type 18, with a high incidence of RF.

Clinical microbiological case: a firm, right infraclavicular mass in an adult woman with connective tissue disease

A 34-year-old non-pregnant female was admitted to our hospital for evaluation of fever, malaise, and a painful mass on the right chest wall, which had first appeared 10 days previously. She denied any local injury, trauma, injection, skin abrasion or infection in her right arm. Her symptoms did not respond to treatment with oral cloxacillin (500mg four times daily for 3 days). She had been diagnosed a year previously with undifferentiated connective tissue disease (UCTD), and did not currently require therapy. Physical examination showed a febrile female in no apparent distress. A firm, tender, non-fluctuant mass was observed under the pectoralis muscle in the right anterior infraclavicular area. The overlying skin was warm but without signs of cellulitis (Figure 1). A chest X-ray revealed a minimal right pleural effusion, not present a year earlier, which was thought to be a reaction to the chest wall process. The evaluation of the mass included a contrastenhanced CT scan (Figure 2). An ultrasonographyguided fine-needle aspiration of the soft tissue tumor yielded blood-stained fluid, and microscopy showed an acute inflammatory infiltrate with some lymphocytes but no malignant cells. A Gram stain of the material did not reveal microorganisms, but b-hemolytic grayish colonies (2–3mm in diameter) grew on sheep’s blood agar culture 24 h later (Figure 3). Three blood cultures, one urine culture and one vaginal culture were all unrevealing.

Eradication of multi-drug resistant Acinetobacter from an intensive care unit.

Acinetobacter baumannii is a gram-negative coccobacillus that causes outbreaks of nosocomial infections in ICUs. Due to resistance to multiple antibiotics, management of clusters of A. baumannii is useful as a model in eradication of multi-drug resistant infections. We outline the evolution of an A. baumannii outbreak, focusing on methods of transmission and multidisciplinary measures aimed at eliminating it from the ICU. Patients in an urban, tertiary care medical center from November 1996 to December 1997 having positive cultures for multi-drug resistant A. baumannii are included in this study. A. baumannii was isolated on blood agar and MacConkey cultures and identified by Vitek panel. Disk diffusion including amikacin, imipenem, polymyxin B, and sulbactam were used to determine resistance. An outbreak of 52 patients (27 infected, 25 colonized) with 68 positive sites began with the transfer of a colonized >50% total body surface area burn patient from an outside hospital. Within 3 days, the index patient was in the burn ICU, coronary care unit, and medical ICU. Soon, clusters of patients with A. baumannii infections sensitive only to polymyxin B were seen in those units and, ultimately, the surgical ICU. On typing, 2 strains were found, PFGE B and C. Given the level of antibiotic resistance, patients with colonization or infection were cohorted and placed on contact isolation. Strict antiseptic measures, such as hand-washing, barrier isolation, equipment and room cleaning, sterilization of ventilator equipment, and dedication of medical equipment to each patient were instituted. Still, positive environmental cultures were found in ventilator water traps, sinks, and bedrails. Sporadic cases continued for a total of 13 months, with 10 deaths resulting from the infections. A. baumannii is a mildly virulent organism that becomes resistant to antimicrobials. Because of multiple antibiotic resistance, strict contact isolation cohorting and antiseptic technique are the primary modes of containment. This outbreak serves as a model of eradication of multi-drug resistant organisms from ICUs. These measures will become of greater importance as nosocomial organisms develop increasing resistance to antimicrobials.

Critical evaluation of a CLIA-waived streptococcal antigen detection test in the emergency department

Study Objective: We compare the performance of a Clinical Laboratory Improvement Amendments (CLIA)-waived antigen detection test (ADT) analyzed in the emergency department and a CLIA moderately complex ADT performed in the hospital microbiology laboratory. Methods: Samples from throat swabs were obtained using a double-headed Culturette II (Becton Dickinson Medical Systems, Sparks, MD) from a consecutive sample of 322 patients 3 years or older who presented to the ED of a university-affiliated pediatric referral hospital with the complaint of sore throat during 1998. One swab was transported to the microbiology laboratory and analyzed using a CLIA moderately complex ADT; negative results were confirmed using sheep blood agar culture. The second swab remained in the ED where a nurse conducted a CLIA-waived ADT. The accepted standard for documentation of group A β-hemolytic streptococcal (GABHS) infection was either a positive moderately complex ADT or culture result. The time of specimen collection, as well as the time the ED results and microbiology laboratory results were available to treating physicians, were recorded. Main outcome measures were concordance (κ statistic), sensitivity, and turnaround time (Mann-Whitney U test). Results: Three hundred twenty-two patients (mean age 7.5 years) had both ADTs performed. One hundred one (31%) patients had documented GABHS in the microbiology laboratory; 83 (82%) had a positive ADT result in the microbiology laboratory, and 18 (18%) had a positive culture result after a negative moderately complex ADT result. In 299 patients or 93% (95% confidence interval [CI] 90.8%, 95.8%) of patients, the waived ADT and the moderately complex ADT results were concordant (κ 0.82; 95% CI 0.78, 0.86; P <.001). The sensitivity of the waived ADT was 80%; the sensitivity of the moderately complex ADT approximated 82% (difference of 2%; 95%CI –3%, 7%). The median times from swab specimen collection to availability of ADT results were 10 minutes (range 3 to 37 minutes) for the waived ADT and 35 minutes (range 5 to 162 minutes) for the moderately complex ADT (P <.001) with a difference of 25 minutes (95% CI 22.4, 27.6 minutes). Conclusion: In this study, an ED CLIA-waived rapid streptococcal throat test performed as well as its equivalent CLIA-regulated laboratory test. Further, the ED test provided results more rapidly than the laboratory test. Our results also validate previous work that negative rapid throat test results in pediatric patients in the ED should be confirmed by standard throat culture. [Roosevelt GE, Kulkarni MS, Shulman ST. Critical evaluation of a CLIA-waived streptococcal antigen detection test in the emergency department. Ann Emerg Med. April 2001;37:377-381.]

Use of urine samples from healthy humans, nephritis patients or other animals as an alternative to foetal calf serum in the culture of Leishmania (L.) donovani in vitro

The effect of supplementing in-vitro cultures of Leishmania donovani with urine was investigated. The parasites were isolated from Bangladeshi patients with visceral leishmaniasis. The urine samples used were collected from healthy human donors, patients with nephrotic syndrome, diabetic nephritis (DN) or diabetes mellitus, a dog and a cow. Promastigotes from blood-agar cultures were inoculated into RPMI-1640 basal medium with 10% heat-inactivated foetal calf serum (FCS) and/or 1%–20% urine. The parasites were then counted in a haemocytometer, on days 2, 4, 5, 6, 7, 8, 10, 12 and 14 post-inoculation. From day 4, the numbers of parasites/ml in cultures containing 5% healthy-human urine but no FCS were at least as high as those in cultures containing 10% FCS but no urine (P = 0.191). The wet weights of parasites harvested from mass cultures of the parasites in RPMI-1640 plus 5% healthy-human urine and in RPMI-1640 plus 10% FCS were practically the same. Multiplication of the parasites in the presence of 5% urine from a DN patient was significantly greater (P < 0.01) than that seen with other urine samples at the same concentration or with 10% FCS. The multiplication seen with 8% canine urine was almost the same as with 5% healthy-human urine. Parasites could be maintained in RPMI-1640 plus 5% healthy-human urine for at least 40 days, sub-culturing every 4 days. Urine may be a better and much cheaper stimulant of Leishmania multiplication in vitro than FCS.

Use of urine samples from healthy humans, nephritis patients or other animals as an alternative to foetal calf serum in the culture of Leishmania (L.) donovani in vitro.

The effect of supplementing in-vitro cultures of Leishmania donovani with urine was investigated. The parasites were isolated from Bangladeshi patients with visceral leishmaniasis. The urine samples used were collected from healthy human donors, patients with nephrotic syndrome, diabetic nephritis (DN) or diabetes mellitus, a dog and a cow. Promastigotes from blood-agar cultures were inoculated into RPMI-1640 basal medium with 10% heat-inactivated foetal calf serum (FCS) and/or 1%-20% urine. The parasites were then counted in a haemocytometer, on days 2, 4, 5, 6, 7, 8, 10, 12 and 14 post-inoculation. From day 4, the numbers of parasites/ml in cultures containing 5% healthy-human urine but no FCS were at least as high as those in cultures containing 10% FCS but no urine (P = 0.191). The wet weights of parasites harvested from mass cultures of the parasites in RPMI-1640 plus 5% healthy-human urine and in RPMI-1640 plus 10% FCS were practically the same. Multiplication of the parasites in the presence of 5% urine from a DN patient was significantly greater (P < 0.01) than that seen with other urine samples at the same concentration or with 10% FCS. The multiplication seen with 8% canine urine was almost the same as with 5% healthy-human urine. Parasites could be maintained in RPMI-1640 plus 5% healthy-human urine for at least 40 days, sub-culturing every 4 days. Urine may be a better and much cheaper stimulant of Leishmania multiplication in vitro than FCS.

Direct analysis and identification of Helicobacter and Campylobacter species by MALDI-TOF mass spectrometry.

Campylobacter jejuni, Campylobacter fetus, and Campylobacter coli were compared with Helicobacter pylori and Helicobacter mustelae by direct analysis of individual cultured colonies in 50% methanol-water with a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS). H. pylori and Campylobacter species from blood agar culture produced unique, complex spectra with over 25 different ions in mass/charge (m/z) range from 2,000 to 62,000. A biomarker for H. pylori was centered around m/z 58,268, and H. mustelae was distinguished from H. pylori by its ions at m/z 49,608 and 57,231. Campylobacters could be distinguished from Helicobacters by their lack of ions around m/z 58,000 and 61,000 as well as distinguishing biomarkers of lower m/z: 10,074 and 25,478 for C. coli; m/z 10,285 and 12,901 for C. jejuni; m/z 10,726 and 11,289 for C. fetus. MALDI-TOF MS is a rapid and direct method for detection of these potentially pathogenic bacteria from culture.

Mycoplasma contamination of canine gastric biopsy samples and cultures of gastric Helicobacter spp.

Helicobacter felis and H. bizzozeronii are canine gastric helicobacters related to H. pylori. The growth of gastric helicobacters requires a complex medium including blood and serum. We found that some of our blood agar cultures were contaminated with mycoplasmas, which were isolated from one biopsy sample and several blood agar cultures of canine gastric helicobacters by PCR or culture method. However, none of our other 18 Helicobacter strains, subcultured 10-15 times since 1990, were found to be contaminated when studied in spring 1996. Nor was horse serum used as a growth supporter found to be contaminated with mycoplasmas. All our mycoplasma isolates grew as pure cultures and as cocultures with H. bizzozeronii on a selective medium containing vancomycin, polymyxin B and trimethoprim used in cultivation of helicobacters. Our data suggest that mycoplasmas occurring on biopsy samples can grow as contaminants on Helicobacter cultures.

Mycoplasma contamination of canine gastric biopsy samples and cultures of gastric Helicobacter spp.

Helicobacter felis and H. bizzozeronii are canine gastric helicobacters related to H. pylori. The growth of gastric helicobacters requires a complex medium including blood and serum. We found that some of our blood agar cultures were contaminated with mycoplasmas, which were isolated from one biopsy sample and several blood agar cultures of canine gastric helicobacters by PCR or culture method. However, none of our other 18 Helicobacter strains, subcultured 10–15 times since 1990, were found to be contaminated when studied in spring 1996. Nor was horse serum used as a growth supporter found to be contaminated with mycoplasmas. All our mycoplasma isolates grew as pure cultures and as cocultures with H. bizzozeronii on a selective medium containing vancomycin, polymyxin B and trimethoprim used in cultivation of helicobacters. Our data suggest that mycoplasmas occurring on biopsy samples can grow as contaminants on Helicobacter cultures.

Comparison of an optical immunoassay technique with two culture methods for the detection of group A streptococci in a pediatric office

For detecting group A β-hemolytic streptococci in an office setting, an optical immunoassay method was compared with two culture methods. The sensitivity and specificity of OIA as compared with 5% sheep blood agar cultures were 91.4% and 95.6%, and as compared with a Todd-Hewitt broth method were 90.4% and 94.1%, respectively. (J PEDIATR 1995;126:931-3)

Bartonella (Rochalimaea) quintanaEndocarditis in Three Homeless Men

Bartonella (Rochalimaea) quintana is the agent of trench fever and is transmitted by the body louse. We searched for this organism in three alcoholic homeless men with endocarditis. Blood samples were cultured on a human endothelial cell line and on blood agar. Bacteria were identified by sequencing the amplified 16S ribosomal RNA gene. The presence of bartonella in tissue was assessed by Gram's staining, immunostaining, and polymerase-chain-reaction amplification. Serologic studies for antibodies to bartonella species were performed by indirect immunofluorescence and Western immunoblotting. B. quintana was isolated from one patient in the blood-agar culture and from the other two patients in the endothelial-cell culture. The organism was also identified by both immunostaining and molecular techniques in the valvular vegetations from the three patients and in a cervical lymph node from one patient. The 16S ribosomal RNA gene sequences of the three isolates were almost identical to that of the prototype strain of B. quintana. High titers of antibodies to B. quintana were detected in all three patients, but so were cross-reacting antibodies to chlamydia species. In all three patients studies were repeatedly negative for antibodies to the human immunodeficiency virus. B. quintana is a cause of endocarditis in homeless patients and may be serologically misdiagnosed as a chlamydial infection.

Evaluation of a new immunologic test kit for rapid detection of group A streptococci, the Abbott Testpack Strep A plus

We compared the Testpack Strep A plus (TPSAP) enzyme-linked immunosorbent assay test for group A beta-hemolytic streptococcal (GAS) antigen rapid detection with blood agar culture in 454 pediatric patients with clinical pharyngitis. Of the 454 patients, 118 (25.9%) had positive oropharyngeal cultures for GAS. TPSAP sensitivity was 89.9% (106 of 118) and specificity was 95.8% (322 of 336). We conclude that the TPSAP is specific enough to indicate treatment for a patient with a positive test but that a negative test should be confirmed by culture.

Evaluating Spatter And Aerosol Contamination During Dental Procedures

A pilot study evaluated the distribution of spatter and aerosols generated by high-speed instrumentation. In the first phase, fluorescent dye was added to the handpiece water supply. In the second, blood agar culture plates were placed in the operatory. Results show that contamination from spatter and aerosol dissemination remains a significant hazard for dental personnel.