Perbandingan Tingkat Resistensi Isolat Klinis Enterobacteriaceae Penghasil Enzim AmpC Beta-Laktamase dan Bukan Penghasil Enzim AmpC Beta-Laktamase Terhadap Sefalosporin

Maria Regina Michelle, Prof. Dr. dr. Osman Sianipar, DMM., MSc., Sp. PK, Subsp P.I. (K), Subsp Onk. K. (K) ; Prof. dr. Budi Mulyono, MM., Sp.PK, Subsp. I.K (K), Subsp. E.M (K) ; Prof. dr. Retno Sutomo, Ph. D., Sp.A., Subsp.

2025 | Tesis | S2 Kedokteran Klinik

Latar Belakang:

Enterobacteriaceae merupakan penyebab berbagai infeksi klinis dan menunjukkan resistensi tinggi terhadap antibiotik ?-laktam, termasuk sefalosporin. Salah satu mekanisme resistensi yang ditemukan adalah produksi enzim AmpC ?-laktamase, yang tidak dapat dihambat oleh inhibitor ?-laktamase konvensional dan berperan dalam inaktivasi banyak antibiotik ?-laktam. Penelitian mengenai perbandingan tingkat resistensi Enterobacteriaceae penghasil dan bukan penghasil AmpC terhadap sefalosporin masih terbatas.

Tujuan:

Mengevaluasi perbedaan tingkat resistensi isolat klinis Enterobacteriaceae penghasil dan bukan penghasil AmpC ?-laktamase terhadap antibiotik golongan sefalosporin.

Metode:

Penelitian ini merupakan penelitian observasional dengan pendekatan cross sectional menggunakan isolat Enterobacteriaceae (K. pneumoniae, E. coli, dan P. mirabilis) dari berbagai sampel klinis. Deteksi AmpC ?-laktamase dilakukan menggunakan uji fenotipe dengan larutan penyangga asam fenil boronat. Uji kepekaan antibiotik dilakukan dengan menggunakan Vitek2. Perbandingan resistensi antara kelompok penghasil dan bukan penghasil AmpC dianalisis menggunakan uji Chi-square. Nilai p < 0>

Hasil:

Sebanyak 52 isolat (42,6%) merupakan penghasil AmpC ?-laktamase. Resistensi terhadap sefazolin, seftriakson, seftazidim, dan sefepim tinggi pada kedua kelompok. Pada isolat penghasil AmpC, resistensi masing-masing adalah 96,2% (sefazolin), 82,7% (seftriakson), 67,3% (seftazidim), dan 44,2% (sefepim). Pada kelompok bukan penghasil AmpC, resistensi masing-masing adalah 97,1%, 91,4%, 52,9%, dan 34,3%. Tidak terdapat perbedaan bermakna pada seluruh antibiotik sefalosporin yang diuji (p > 0,05).

Simpulan:

Perbandingan tingkat resistensi antara isolat penghasil dan bukan penghasil AmpC b-laktamase terhadap sefalosporin tidak menunjukkan perbedaan yang bermakna secara statistik.

Background:

Enterobacteriaceae are among the most common causes of clinical infections and often exhibit high levels of resistance to ?-lactam antibiotics, particularly cephalosporins. One notable resistance mechanism is the production of AmpC ?-lactamase, an enzyme not inhibited by conventional ?-lactamase inhibitors that contributes to the inactivation of many ?-lactam agents. However, studies comparing resistance patterns between AmpC-producing and non–AmpC-producing Enterobacteriaceae against cephalosporins remain limited.

Objective:

To evaluate the differences in resistance levels to cephalosporin antibiotics between clinical isolates of AmpC ?-lactamase–producing and non-producing Enterobacteriaceae.

Method:

This observational cross-sectional study utilized Enterobacteriaceae isolates (K. pneumoniae, E. coli, and P. mirabilis) obtained from various clinical specimens. Detection of AmpC ?-lactamase was performed phenotypically using phenylboronic acid buffer solution. Antibiotic susceptibility testing was conducted using the Vitek2 system. Comparisons of resistance rates between AmpC-producing and non-producing groups were analyzed using the Chi-square test. A p-value < 0>

Result:

A total of 52 isolates (42.6%) were identified as AmpC ?-lactamase producers. High resistance rates to cefazolin, ceftriaxone, ceftazidime, and cefepime were observed in both groups. Among AmpC-producing isolates, resistance rates were 96.2% (cefazolin), 82.7% (ceftriaxone), 67.3% (ceftazidime), and 44.2% (cefepime). In the non-AmpC-producing group, resistance rates were 97.1%, 91.4%, 52.9%, and 34.3%, respectively. No statistically significant differences were found in resistance rates for any of the tested cephalosporins (p > 0.05).

Conclusion:

Clinical isolates of AmpC ?-lactamase–producing Enterobacteriaceae tend to show higher resistance to cefazolin, ceftazidime, and cefepime. In contrast, non-AmpC-producing isolates exhibited higher resistance to ceftriaxone. However, overall comparisons between the two groups did not show statistically significant differences in resistance to cephalosporin antibiotics.

Kata Kunci : Enterobacteriaceae, infeksi, AmpC beta-laktamase, resistensi