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Neisseria gonorrhoeae is an etiologic agent of gonorrhoea, one of the most common sexually transmitted diseases caused by bacteria. For many years, infections caused by N. gonorrhoeae were considered to be relatively easy to treat; however, resistance has emerged successively to all therapeutic agents used in treatment of the disease, e.g., penicillin, ciprofloxacin or azithromycin. Currently, the global problem is the emergence and a threat of spread of N. gonorrhoeae strains resistant to extended-spectrum cephalosporins (ESC), such as injectable ceftriaxone and oral-used cefixime. Especially, dangerous are multi-resistant strains resistant simultaneously to ESC and azithromycin. Three strains with high-level resistance to azithromycin and resistant to ESC were first time isolated in 2018. Moreover, in 2018, the first ESBL was described in N. gonorrhoeae and that makes the threat of appearing the ESBL mechanism of resistance in N. gonorrhoeae more real, even though the strain was sensitive to ceftriaxone. Molecular typing revealed that variants resistant to ESC occurred also among strains belonging to epidemic clonal complex CC1 (genogroup G1407) distinguished in NG-MAST typing system. The G1407 genogroup, in particular the ST1407 sequence type, is currently dominant in most European countries. The presence of different mechanisms of drug resistance significantly affects clinical practice and force changes in treatment regimens and introduction of new drugs.

Introduction: Gonorrhoea is one of the most common sexually transmitted diseases in the world. Fast and effective laboratory diagnostics of the infection is very important. The aim of the study was to compare Real-Time PCR and bacterial culture in diagnostics of Neisseria gonorrhoeae infections in patients of Department of Dermatology and Venereology Medical University of Warsaw., Methods: The urethral, cervical, anal and pharyngeal specimens from 93 patients of Department of Dermatology and Venereology Medical University of Warsaw were examined by two methods. The bacterial culture was performed on chocolate agar plates with antibiotics in the 5% CO2 atmosphere at 37°C. N. gonorrhoeae was identified by colony-morphology, Gram stain and oxidase reaction, followed by carbohydrate utilization test. The DNA Bact Extra Pure Kit (Euroclone®) to isolate DNA was used. Real-Time PCR DUPLICα® Real-Time Neisseria gonorrhoeae 2nd Generation Detection Kit (Euroclone®) was performed using Smart Cycler® Dx., Results: In 85.9% of results of Real-Time PCR and culture were identical. The remaining 14.1% of samples were culture negative and PCR positive. The results ofthe Real-Time PCR and culture were more often concordant in the case of samples obtained from men (96.8%) than from woman (85%). In patients after treatment with antibiotics the concordance of the results obtained with these two methods was 81%., Conclusions: In laboratory diagnostics of N. gonorrhoeae infections, Real-Time PCR was more sensitive than the culture, but in some cases it was less specific.

Introduction: Azithromycin is one of the most commonly used macrolide antibiotics. As other macrolides it inhibits bacterial proteins synthesis by binding with V domene of bacterial 23S rRNA. Resistance to azithromycin can be related to: 1. Mutations in gene encoding 23S rRNA. Significant effect on azithromycin MIC (minimal inhibitory concentration) is not observed when the mutation occurs only in 1 allele. In case of mutations occurring in 4 alleles, more common mutation C2611T is associated with MIC 2-16 mg/L and the second mutation A2059T results in high level resistance to azithromycin MIC > 256 mg/l 2. Over- production of membrane pumps proteins MtrCDE and MacAB, that remove antibiotics from bacterial cells. The mechanism is not able to cause azithromycin resistance itself but coexisting with other mechanisms of resistance can additionally increase MIC. 3. Synthesis of 23S rRNA methylases ErmB, ErmF, ErmC, ErmA. These enzymes cause demethylation of adenine (A2058) in V domain of 23S rRNA. The mechanism was common in the past, but it has been replaced by mutations in in V domain of 23S rRNA. Nowadays 23S rRNA methylases are very rare in N. gonorhoeae., Methods: Sixty five Neisseria gonorrhoeae strains isolated from patients of the Department of Dermatology and Venereology in Warsaw in the second half of 2012 and first of 2013 were investigated. The strains were cultured on chocolate agar plates in a 5% CO2 atmosphere at 37 °C and identified by colony morphology, Gram staining and oxidase reaction, followed by carbohydrate utilization test. Azithromycin susceptibility was determined by E-Tests (bioMerieux). Bacteria were incubated at 37°C in 5% CO2 for 24 h on chocolate agar plates. Tests were performed according to producers recommendations. The results (sensitive or resistant) were interpreted according to EUCAST recommendations., Results: The MIC of azithromycin in investigated strains ranged from 0,064 to 4 mg/L, MIC50 = 0.5 mg/L, MIC90 = 2 mg/L. It was shown that only 38.5% of the strains were sensitive to azithromycin according to EUCAST criteria from 2014 year and 89.3% of the strains were sensitive to azithromycin according to CDC criteria from 2014 year., Conclusions: The percentage of azithromycin resistant Neisseria gonorrhoeae strains is increasing in Poland and the antibiotic should not be used in monotherapy as gonorrhoea patients. It should only be used in combination with ceftriaxone or cefixime.

Introduction: Ciprofloxacin is commonly used in Poland specially for the treatment of urinary tract infections including urethritis. Patients are often treated without pathogen identification and antimicrobial resistance tests. Neisseria gonorrhoeae infection is one of the most common causes of urethritis in Poland. The resistance of bacteria to a wide range of antibiotics including ciprofloxacine makes the therapy of gonorrhoea more difficult. The mechanism of ciprofloxacine action depends on inactivation of bacterial topoisomerase II (gyrase) and topoisomerase IV. A resistance to ciprofloxacine occurring in Neisseria gonorrhoeae is mainly due to mutations in bacterial gyrA (encoding topoisomerase II) and/or parC (encoding topoisomerase IV ) genes. High level resistance is an effect of combination of three or four mutations. Another, less important mechanism of ciprofloxacin resistance, that can coexist with mutations in gyrA and parC genes related to the overproduction of membrane pumps proteins., Material and Methods: 65 Neisseria gonorrhoeae strains isolated from patients of Department of Dermatology and Wenereology in Warsaw in the second half of 2012 and first of 2013 was investigated. The strains were cultured on chocolate agar plates in a 5% CO2 atmosphere at 37 degrees C and identified by colony morphology, Gram stain and oxidase reaction, followed by carbohydrate utilization test. Ciprofloxacin susceptibility was determined by E-Tests (bioMerieux). Bacteria were incubated at 35 degrees C in 5% CO2 for 24 h on chocolate agar plates. Tests were performed according to producers recommendations. The results (sensitive or resistant) were interpreted according to EUCAST recommendations., Results: The MIC (Minimal inhibitory concentration) of Ciprofloxacin in investigated strains ranged from 0,002 to > 32 mg/L, MIC50 = 8 mg/L, MIC90 = > 32 mg/L. It was shown that only 38.5% of the strains were sensitive to ciprofloxacin according to EUCAST criteria from 2013 year., Conclusions: Due to the high percentage of ciprofloxacin resistant Neisseria gonorrhoeae strains (more than 61%) the antibiotic should not be used for the treatment of gonorrhoea in Poland.

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Introduction: One of two main mechanisms of resistance in tetracycline-resistant Neisseria gonorrhoeae (TRNG) is associated with the presence of TetM protein responsible for actively blocking of the tetracycline target site in the 30S ribosomal subunit. This mechanism is encoded by conjugative plasmids. The second mechanism is chromosomal in nature and due to mutations in specific genes. Aim: To determine the incidence and type of tetM determinants in TRNG strains isolated from patients presenting with gonorrhea infection to the Dermatology and Venereology Clinic in Warsaw in 2012-2013. Material and methods: Tetracycline and doxycycline susceptibility was determined by E-Tests. The presence and type of the tetM gene were determined by polymerase chain reaction. Results: Tetracycline resistance was detected in 50.8% of the evaluated strains. The TRNG strains containing the tetM plasmid constituted 13.8% of all the evaluated strains. Dutch type tetM constituted 12.3% and American type tetM 1.5% of all the evaluated strains. In the remaining TRNG strains, resistance to tetracyclines was presumably chromosome-encoded. The minimal inhibitory concentration (MIC) of tetracycline ranged from 0.25 to 32.0 mg/l, MIC50 = 2.0 mg/l, MIC90 = 32.0 mg/l. The MIC of doxycycline ranged from 0.25 to 32.0 mg/l, MIC50 = 4.0 mg/l, MIC90 = 16.0 mg/l. Conclusions: Unlike most of European countries, in 2012-2013 in Poland, the Dutch type tetM was found to be much more common than the American type. Minimal inhibitory concentration values of tetracycline and doxycycline were similar, with doxycycline exhibiting a somewhat lower effectiveness in vitro than tetracycline towards chromosome-mediated tetracycline resistant strains of N. gonorrhoeae. [ABSTRACT FROM AUTHOR]

The article "Multiresistant Neisseria gonorrhoeae: a new threat in second decade of the XXI century", written by Beata Młynarczyk‑Bonikowska, Anna Majewska, Magdalena Malejczyk, Grażyna Młynarczyk, Sławomir Majewski was originally published electronically on the publisher's internet portal (currently SpringerLink) on December 04, 2019 without open access. [ABSTRACT FROM AUTHOR]