Rapid high-throughput processing of tissue samples for microbiological diagnosis of periprosthetic joint infections using bead-beating homogenization

ABSTRACT

Enrichment of periprosthetic tissue samples in blood culture bottles (BCBs) for microbiological diagnosis of periprosthetic joint infections (PJI) is more reliable than the use of an enrichment broth. Nevertheless, the extremely time-consuming homogenization of the samples for BCB processing has so far limited its use, especially in high-throughput settings. We aimed to establish a highly scalable homogenization process of tissue samples for long-term incubation in BCBs. A protocol for homogenization of tissue samples using bead beating was established and validated. In a second step, the use of the homogenate for enrichment in BCBs was compared to the use of thioglycolate broth (TB) in terms of diagnostic accuracy using clinical tissue samples from 150 patients with suspected PJI. Among 150 analyzed samples, 35 samples met the microbiological criteria for PJI. Using BCB, 32 of 35 (91.4%) PJI were detected compared to 30 of 35 (85.7%) by TB. The use of BCB had a lower secondary contamination rate (2/115; 1.7% vs 4/115; 3.5%) but the trend was not significant due to low numbers of samples (P = 0.39). The time to process a batch of 12 samples using the established homogenization method was 23 ± 5 min (n = 10 batches). We established and validated a homogenization workflow that achieves the highest sensitivity in the microbiological diagnostic of PJI. The enrichment of the tissue homogenate in BCBs showed equally good results as the use of enrichment broth and allows semi-automated high-throughput processing while demonstrating lower contamination rates in our study.

INTRODUCTION

Tissue specimens collected during surgery or by fine-needle biopsy are among the most meaningful materials that can be obtained for microbiological culture. Therefore, the highest standards of processing and analysis should be applied to the microbiological analysis of such samples. The examination of joint tissue according to the German quality standards in microbiological–infectiological diagnostics (1) is based on the cultivation of bacteria on solid, non-selective agar plates and additionally in enrichment broths. An incubation period of 14 days is required to enable cultivation even of slow-growing bacteria that would otherwise remain undetected (2).

The use of classic enrichment broth, such as thioglycolate bouillon (TB), is labor intensive involving daily inspection over a period of 14 days and subculturing in case of suspected bacterial growth (turbidity). Besides the high workload, this method bears the risk of contaminating during the inoculation procedure and during sub-culturing because the broth tube has to be opened and closed manually leading to 10% to 30% false-positive results (3, 4).

Thus, several studies in recent years report the advantages of using blood culture bottles (BCB) for the enrichment of culture tissue homogenate from the joints and bones in periprosthetic joint infections (PJI) (5–7). The use of BCBs allows continuous automated growth monitoring as well as the possibility of incubating larger sample volumes than on solid media. In addition, the presence of lytic agents in the BCB promotes the release of intracellular microorganisms. By using blood culture semiautomatic monitoring systems, a reduced time to culture positivity has been observed, when compared to conventional agar plates and broth methods (4). Furthermore, the use of BCB reduces manual handling and is less time-consuming than the use of conventional enrichment broth.

To inoculate tissue samples from joints in a blood culture system, the sample has to be almost fully homogenized and liquid. The existing recommendations for homogenizing tissue samples range from the use of sterile mortar and pestle to any form of tissue grinder (1). These methods are predominantly manual techniques and therefore are highly prone to contamination because of extensive open handling of specimens and consumables. Furthermore, most of the homogenization methods only allow the processing of one sample at a time.

In our study, we aimed to establish and validate a homogenization process that allows a fast, effective, and contamination-free high throughput of tissue samples for long-term incubation in a BCB system and validate its diagnostic accuracy in clinical tissue samples.

MATERIALS AND METHODS

Homogenization process using Precellys Evolution

For the homogenization of orthopedic tissue samples, we used Precellys Evolution (Bertin Technologies, Montigny-le-Bretonneux, France) with Precellys lysing kit (CK28-7 mL, Bertin Technologies, Montigny-le-Bretonneux, France) consisting of a 7-mL tube prefilled with approximately 35 ceramic beads each having a diameter of 2.8 mm. According to the manufacturer’s instructions, the tubes in the lysing kit were autoclaved, DNAse free, and optimized for the homogenization of tissue and bones. For use with orthopedic tissue samples, each Precellys lysing kit was prefilled with 3.0 mL of sterile 0.9% NaCl in a class 2 microbiological safety cabinet. Homogenization was performed in batches of 12 samples using Precellys Evolution at 5,500 rpm for 20 s.

Sterility of the Precellys lysing kit CK28-7 mL

The sterility of the Precellys lysing kit was tested by adding 3 mL of thioglycolate broth to an empty Precellys lysing kit (instead of 3.0 mL of NaCl) under a sterile workbench and incubating the tubes at 36°C ± 1°C for 14 days. After 5 days, 10 days, and at the end (day 14) thioglycolate broth from each tube was streaked out on Columbia agar supplemented with 5% sheep blood, chocolate agar, and Schaedler agar (Beckton Dickinson, Franklin Lakes, USA). Inoculated plates were incubated at 36°C ± 1°C for 3 days under the respective conditions. After, incubation plates were checked for bacterial growth.

Viability of bacteria after homogenization by Precellys Evolution

According to the manufacturer, the composition of the ceramic beads should not lead to the disruption of microorganisms (i.e., bacteria or fungi). Nevertheless, the friction of the beads leads to heat generation, which could limit the viability of the bacteria.

To rule this out, viability of test strains was assessed by determining the recovery rate [colony-forming units (CFU)/100 µL] of Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Haemophilus influenzae DSM 11970, Candida albicans ATCC 90028, Bacteroides fragilis ATCC 25285, and Cutibacterium acnes (laboratory strain) before and after homogenization by Precellys Evolution with 5,500 rpm for 20 s colonies of overnight-grown bacterial and fungal cultures were suspended either in 0.9% NaCl (aerobic bacteria and fungi) or in thioglycolate broth (anaerobic bacteria) to a McFarland density of 0.5 (aerobic bacteria) or 0.6 (anaerobic bacteria) or 1.0 (fungi). Respective suspensions were further diluted 1:10.000 to a suspension of approximately 10⁴ CFU/mL to reach a countable number of CFU on the resulting agar plate.

Thirty microliters of each bacterial suspension was added to the Precellys lysing kit tube (containing 3 mL of 0.9% NaCl). Per test strain, 10 replicates were performed. Using a spiral plater (IUL Eddy Jet 2, IUL-Instruments, Barcelona, Spain) 100 µL of the final suspension was streaked on Columbia agar supplemented with 5% sheep blood (BD) in a linear mode before and after homogenization at 5,500 rpm for 20 s. Agar plates were incubated at 36°C ± °C for 24 h /48 h under aerobic/anaerobic conditions, respectively. CFU on the agar plates were counted, documented, and compared. The temperature of the homogenized samples was measured directly after homogenization using an infrared dual-laser thermometer.

Assessment of diagnostic accuracy of the homogenization process with enrichment in BCB bottles

Study design

From February to March 2020, orthopedic tissue samples that were submitted to the Labor Dr. Wisplinghoff (Cologne, Germany) for microbiological diagnostic of PJI were included in the study. To diagnose PJI, several samples are usually sent in for one patient to distinguish contamination from a genuine infection. As our study is not concerned with a clinical but a technical question, we only included one sample per patient in the analysis (to avoid duplication). In total, 150 patients (one sample each) were included in the study.

For the classification of PJI, however, it is necessary to consider the results of all samples for a patient. Thus, although only one sample per patient was used for testing and evaluation of the homogenization process, the results of all samples submitted for a patient from the corresponding surgery were considered by a medical microbiologist to classify whether a sample/patient had a PJI from a microbiological point of view (see below).

Samples had to be at least 1.0 cm³ to be selected for the study. The BCB-based method (including homogenization of the samples) was run in parallel with the conventional enrichment method in thioglycolate broth (see Fig. 1). The processing of the samples and the preparation of the solid agar media and enrichment media of both arms (thioglycolate broth and BCB) were carried out under a class 2 microbiological safety cabinet.

Fig 1.

Study design clinical samples. Abbreviations: BCB, blood culture bottles.

Each sample was cut into two cubes of 0.5 cm³. One cube was placed in a prefilled, sterilized Precellys lysing kit tube for homogenization in the Precellys Evolution homogenizer. Of the homogenized sample, 0.7 mL each was inoculated, respectively, into an aerobic and anaerobic BCB using a sterile syringe. Additionally, a part of the homogenate was used to inoculate solid agar media (Columbia agar supplemented with 5% sheep blood, chocolate agar, and Schaedler agar).

The other cube was chopped using a sterile scalpel. Using a sterile swab, the crushed material was streaked out onto solid agar media (Columbia agar supplemented with 5% sheep blood, chocolate agar, and Schaedler agar) and inoculated into 5 mL of thioglycolate broth (standard workflow).

Enrichment broths were incubated at 36°C ± 1°C for 14 days and inspected daily by a microbiologist to check for potential bacterial growth (i.e., turbidity). BCB were put into the BACT/Alert 3D (BioMerieux. Marcy l'etoile, France), and incubation time was set to 14 days. In case of a positive blood culture or in case of suspicion of growth in an enrichment broth, 100 µL of the broth or positive blood culture, respectively, was subcultured onto Columbia agar supplemented with 5% sheep blood, chocolate agar, and Schaedler agar. Aerobic agar plates were incubated at 36°C ± 1°C under aerobic conditions. Schaedler agar was incubated in an anaerobic jar system (Anoxomat Mark II, Advanced Instruments, Norwood, MA, USA) also at 36°C ± 1°C. Plates were read at 24 and 48 h. Additionally, all broth and BCBs were subcultured at the end of the incubation period irrespective of the presence of a positive signal in the BCB or turbidity in thioglycolate broth. Conventional microbiological methods for identification of bacteria (i.e., matrix-assisted laser desorption ionization–time of flight mass spectrometry and phenotypic tests) were applied according to the German standards of microbiology.

Time to positivity

The time to positivity (TTP) was assessed as the time from the sample inocculation (either to BCB or to enrichment broth) until flagging positive (either by the BACT/Alert or by the microbiologist detecting turbidity).

Hands-on time

The time to process 12 samples from receipt (already placed in a rack of 12) to incubation (last BCB in BACT/ALERT) by a medical technical assistant (MTA) was assessed with five different MTAs (two runs per MTA).

Diagnosis of a periprosthetic joint infection

For PJI categorization, a medical microbiologist analyzed the results of all samples from a patient together to categorize the sample included in the study as PJI or not. Samples that were not examined as part of the study were processed in the same way as the thioglycolate broth arm. The bacteriological results of the samples included in the study were considered positive in terms of PJI if bacterial growth was a strict pathogen (such as Staphylococcus aureus, Pseudomonas aeruginosa, or Enterobacterales) or if the detected pathogen was a skin commensal (such as coagulase-negative staphylococci), and in total, two (or more) cultures from the corresponding operation of the patient yielded the same pathogen. Growth of skin commensal in only one culture or growth of different skin commensals in different cultures of one patient was considered as microbial colonization or contamination. This definition is based on the clinical practice guidelines by the Infectious Diseases Society of America (8).

Statistical analysis

Statistical analysis was performed using MedCalc for Windows, version 19.4 (MedCalc Software, Ostend, Belgium). Descriptive statistics were based on percentages and frequencies for categorical variables as well as means and standard deviation (SD) or medians and interquartile ranges (IQRs) for continuous variables (TTP). For comparison of categorical data, proportions were compared, and the significance level, or P-value, was calculated using the chi-squared test with n − 1 degrees of freedom. For analysis of the continuous data (TTP), the Mann–Whitney test was used.

RESULTS

Sterility of the Precellys lysing kit tubes CK28-7 mL

Ten empty Precellys lysing kit tubes were filled with 3 mL of thioglycolate broth, incubated for 14 days at 36°C ± 1°C and then streaked out at days 5, 10, and 14.

We found growth of bacteria in 80% of the tubes (8/10) after at least 5 days of incubation. Most frequently, Bacillus spp. (7/8) [Bacillus licheniformis (2), Bacillus pumilus (2), Bacillus niacini (1), Bacillus simplex (1), Bacillus megaterium (1), and Micrococcus luteus (1/8)] were recovered from the tubes.

Adaptation of the protocol

To avoid contamination of the samples, the Precellys Lysing kit tubes had to be sterilized before use. To reduce later handling of the tube, we prefilled the tubes with 3 mL of 0.9% NaCl before sterilization by gamma ray. For sterilization, 50 prefilled lysing kit tubes were packed together in transparent DuPont Tyvek foil (ISO 11607) and irradiated with 17.72-kGy gamma ray. Sterilization was controlled and documented with process indicators as well as bioindicators.

To validate the sterilization process for our needs, we inoculated the whole fluid (3 mL of 0.9% NaCl) of 40 sterilized tubes in a set of blood culture bottles (1.5 mL each) and found no growth after 14 days of incubation in any of the samples (contamination 0/80 BCB).

Viability of bacteria before and after homogenization by sterilized Precellys lysing kits

Six different microorganisms were tested each in 10 replicates (n = 60). The temperature of the homogenate was 30.1°C ± 0.9°C (n = 60) directly after homogenization for 20 s at 5,500 rpm. Of note, when using 2 × 20 s with a break of 30 s between the two runs, the temperature at the end was as high as 42°C, and the recovery from the bacterial suspensions was significantly decreased (data not shown).

To assess the viability in more detail, we compared the recovery of the six different microorganisms from the prefilled and sterilized Precellys lysing kit tubes before and after homogenization. There was no significant difference in any of the analyzed strains (see Table 1).

TABLE 1.

Recovery of microorganisms from spiked prefilled and sterilized Precellys lysing kit tubes before and after homogenization for 20 s at 5,500 rpm^a

Strain (McF) (n = 10)	CFU/100 µL before Precellys (mean ± SD)	CFU/100 µL after Precellys (mean ± SD)	P-value
S. aureus (ATCC 29213) (McF 0.5)	87.33 ± 12.81	86.22 ± 6.04	0.8
E. coli (ATCC 25922) (McF 0.5)	50.9 ± 4.75	47.4 ± 6.95	0.2
H. influenza (DSM 11970) (McF 0.5)	76.20 ± 8.93	80.4 ± 11.95	0.38
C. albicans (ATCC 90028) (McF 1)	2.4 ± 1.78	3.4 ± 1.26	0.163
B. fragilis (ATCC 25285) (McF 0.6)	59.0 ± 7.02	54.60 ± 6.7	0.17
Cutibacterium acnis (LS 1) (McF 0.6)	54.3 ± 8.62	61.20 ± 9.3	0.08

^a McF, Mc Farland standard; CFU, colony-forming units; SD, standard deviation; LS, laboratory strain.

Final protocol for the homogenization of orthopedic tissue samples

The workflow of the final homogenization process of tissue samples is shown in Fig. 2.

Fig 2.

Semi-automated high-throughput homogenization of orthopedic tissue samples for enrichment in blood culture bottles. (A) Adding 3 mL of sterile 0.9% NaCl to Precellys lysing kit CK28 (7 mL). (B) Sterilization of the Precellys lysing kit (prefilled with 3 mL of 0.9% NaCl) using gamma ray. (C) Adding the biopsy to the sterilized lysing kit under a class 2 microbiological safety cabinet. (D) Homogenization of the sample using Precellys Evolution for 20 s at 5,500 rpm in a batch of 12 samples. (E) Aliquoting the fluid sample in a sterile empty tube (0.5 mL) for the automatic preparation of agar plates and Gram staining and in aerobic and anaerobic blood culture bottles (each 0.7 mL).

Assessment of diagnostic accuracy of the homogenization process

Of the 150 included samples, 35 (23.2%) met the microbiological criteria for PJI; the other 115 samples were not likely to be from a PJI (see Fig. 3). Most of the samples were recovered from the hip joint (n = 62, 41.3%) and knee joint (n = 58, 38.7%) followed by the spine (n = 8, 5.3%), upper ankle (n = 6, 4%), unknown localization (n = 6, 4%), shoulder (n = 5, 3.33%), and elbow (n = 5, 3.33%).

Fig 3.

Flowchart—determination of infection vs contamination. Abbreviations: n, no. of samples; PJI, periprosthetic joint infections; BCB, blood culture bottles; IDSA, Infectious Diseases Society of America.

Using BCB, 32 of 35 (91.43%) PJI were detected compared to 30 of 35 by TB (85.71%) (P = 0.46). The relevant organisms detected by only one of the according enrichment methods are listed in detail in Table S1. No additional organisms were found by final subculturing of the enrichment media after 14 days of incubation. The use of BCB had a lower secondary contamination rate, but the trend was not significant due to low numbers (2/115; 1.7% vs 4/115; 3.5%; P = 0.39). The organisms detected as contaminants in the samples are listed in Table S2. All performance characteristics of both methods are shown in Table 2.

TABLE 2.

Performance characteristics of the use of BCB and enrichment broth to detect microorganisms in samples from patients with joint infections

Performance characteristics	Blood culture bottles % (95% CI)	Enrichment broth % (95% CI)b
Sensitivity	91.43 (76.94% to 98.20%)	85.71 (69.74% to 95.19%)
Specificity	98.26 (82.86% to 99.79%)	96.52 (91.33% to 99.04%)
Positive predictive valuea	94.11 (80.11% to 98.34%)	88.23 (73.90% to 95.19%)
Negative predictive valuea	97.42 (92.75% to 99.11%)	95.70 (90.80% to 97.22%)

^a These values depend on prevalence of PIJ in our collective (23.3%).

^b CI, confidence interval.

A total of 49 different bacterial strains were recovered from 150 samples. Methicillin-susceptible Staphylococcus aureus (n = 13) was the most frequently recovered bacterial strain followed by Staphylococcus epidermidis (n = 6) (see Fig. S1).

Growth on the solid culture media (n = 21) was confirmed in all cases by both enrichment arms. In 16 samples, growth was only found by enrichment media. The TTP of all positive thioglycolate broth was 72.0 ± 63.3 h compared to 16.0 ± 10.2 h in all positive aerobic BCB and 28.2 ± 32.6 h in all positive anaerobic BCB.

To compare the TTP between BCB and thioglycolate broth, only samples with no growth on solid agar media (n = 16), and in case of both BCB positive, only the first BCB were considered for analysis. The TTP of BCB in samples with no growth on solid agar media was significantly lower compared to the TTP of thioglycolate broth (P = 0.0004) (Fig. 4).

Fig 4.

Comparison of the time to positivity in BCB and enrichment broth. For calculation and visualization of the difference in TTP, only the TTP of samples with no growth on solid agar media (n = 16) and only the first positive BCB (if both positive) were consider for this graph. The horizontal line in each box indicates the median, whereas the top and bottom lines represent the 75th and 25th centiles, respectively. The “whiskers’” extend to the minimum and maximum value per group. The red dot represents far out value that was higher than the upper outer fence.

Hands on time

The time to process a batch of 12 samples was 23 ± 5 min (n = 10 batches, two measurements per medical technical assistant). The most time-critical parameter in this workflow was the preparation of the biopsy for the homogenization procedure.

DISCUSSION

Solid or semisolid tissue samples must be liquified before further microbiological processing to ensure that bacteria are evenly distributed in the sample for the preparation of different agar plates and enrichment media. In this way, sensitivity can be increased as also bacteria that may only be present inside the biopsy can be detected (9). Further increase in sensitivity in the diagnostic of joint infections can be achieved when the homogenization is combined with the use of BCB (7). Homogenization of tissue samples is extremely time consuming and requires experienced staff. We here present a homogenization protocol for high-throughput processing of orthopedic tissue samples using Precellys Evolution.

In general, the homogenization process could harm the microorganisms in the sample and thus lower the sensitivity of the diagnostic workflow (10). We could confirm the results of Redanz et al. that there is no harm to the microorganisms due to the homogenization by the Precellys instrument (9). Additionally, in our study, the sensitivity of the homogenized samples in blood culture bottles for the detection of periprosthetic joint infections in clinical samples was even higher compared to the use of enrichment broth. That is in line with other studies that recently have shown that the use of blood culture bottles, instead of nutrient broth, leads to better sensitivity in the diagnosis of PJI (7).

A higher sensitivity is more prone to contamination. We checked the purity of the bead-filled tubes used in our study and observed the growth of environmental bacteria in 80% of the tubes. The manufacturer of the Precellys lysing kits does not explicitly guarantee sterility, but states that the tubes have been autoclaved. Since we found mainly spore formers in the tubes, we assume that the autoclaving process of the tube manufacturer was not sufficient to eliminate spores adequately. We, therefore, strongly recommend checking the sterility of all tubes before using them for homogenization in microbiology. Interestingly, Redanz et al. did not experience a higher contamination rate when using a Precellys lysing kit with enrichment broth (9). That could either be due to the different kits used (CK28-7 mL vs CK14/28 2 mL) or because a higher volume for enrichment was used in our study (1.4 mL (0.7 in each BCB) vs 100 µL). We performed filtration experiments (data not shown in detail) and recovered 1 to 10 CFU/mL from the Precellys lysing kits CK28-7 mL. If only 100 µL is used for inoculating the enrichment broth, the probability to transfer bacteria is low, and therefore, the contamination might not be such a problem if kits are not used with BCB.

Recently, Rieber et al. published a homogenization protocol using Precellys Evolution using 15-mL tubes (and 3–5 mL of 0.9% NaCl). The authors also sterilized the tubes before use and could find reliable processing of tissue samples for the diagnosis of PJI but did not use any enrichment method (11).

Practical aspects

We were able to show that by using BCBs, the time to positivity was significantly shorter compared to enrichment broth. This is in line with the results of other research groups. Minassian et al. even suggest that by using BCB, the total time of incubation could be reduced to 9 days instead of the required 14 days in enrichment broth (5). Our results are supporting this theory as the latest detection of a pathogen in a BCB was after 163 h (6.8 days).

In addition, the use of BCBs can significantly reduce the workload in the laboratory by eliminating the need for daily inspection of enrichment media. Furthermore, when using enrichment broth, a high amount of negative samples is streaked out every day: bacterial turbidity is measured optically and can only be poorly distinguished from negative samples especially if the samples contain blood. This makes the use of enrichment broth more prone to contamination as a lot of samples have to be opened and closed unnecessarily. In our study, we found four samples in which the enrichment broths were contaminated compared to two samples in which the contamination was found in the BCBs.

In the past, several mechanical-homogenization systems were used to process and homogenize tissue samples and show, in general, a higher sensitivity compared to manual techniques or direct culture (12), but most of them can only process a few samples at a time (10, 13) or have a volume that is too low for the diagnostic of periprosthetic joint infections (7, 9).

The most time-critical parameter in our workflow was the transfer of the sample from the transportation vessel into the Precellys lysing kit tube. Since biopsies of different sizes are sent in from the operating theaters, they must first be cut into the desired size in a biosafety cabinet.

This step could be optimized by the surgeon taking the biopsy in an optimal size and filling it directly into the tube of the Precellys lysing kit, as it was done in the study by Rieber et al. (11). This would not only reduce secondary contamination but also save time. Therefore, the Precellys Lysing Kit tubes need to be prepared in double-sealed units of, for example, five with 0.9% NaCl prefilled and sterilized tubes for PJI diagnostics. For use in the microbiological routine, this needs to be done according to the European Medical Device Regulation, and the authors would very much welcome the commercial availability of such product.

There are other reliable mechanical-homogenization systems, such as the ULTRA-TURRAX system (14), where the bead-based mortars can be purchased already prepared as described above. However, these systems are, first, very expensive and, second, do not yet allow more than one sample to be processed on one device, which greatly restricts upscaling. The advantage of the ULTRA-TURRAX system’s sample vessels, however, is that they are commercially available as sterile double-packed units and thus already suitable for direct use in the operating theater.

Our study had some limitations. First, we only applied microbiological criteria for PJI, and no clinical patient data were available. This could impact the categorization of samples in PJI positive or negative. For the two arms of the study, different parts of the biopsy were used, and for the thioglycolate broth arm, the biopsy was not fully homogenized but only cut in small pieces. If a tissue sample harbors a very low bacterial load, the distribution of the bacteria in the sample may have an impact on the detection rate in any of the used algorithms.

We found one sample with Candida albicans only recovered by the thioglycolate bouillon arm and not by homogenization plus BCBs. In general, the homogenization process was proofed not to harm filamentous fungi (Table 1). Nevertheless, we only inoculated approximately 50% of the sample to the BCBs (1.4 of 3 mL). Maybe a higher volume could reach better performance characteristics; but this was not tested in our study.

Our study is a single-center study, and the number of PJI is small. Thus, results are not generalizable. The workflow would have to be validated for the use in other laboratories.

Nevertheless, we here describe a workflow that is fulfilling all criteria to reach the highest sensitivity in the microbiological diagnostic of PJI (the use of mechanical homogenization in combination with enrichment in blood culture bottles). Our laboratory is processing up to 150 samples a day, and 12 samples can be processed within less than 30 min.

In conclusion, the Precellys Evolution homogenizer used with sterilized CK28-7 mL lysing kits is suitable for rapid high-throughput processing of tissue samples for microbiological diagnosis.

ETHICS APPROVAL

The study has been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. For the improvement of an existing methodological procedure, no ethical approval is needed in the federal state of North Rhine—Westphalia.

SUPPLEMENTAL MATERIAL

The following material is available online at https://doi.org/10.1128/jcm.01486-23.

Tables S1 and S2 and Figure S1. jcm.01486-23-s0001.pdf.

Supplemental tables and figure.

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