Thesis (Ph.D)-Cairo University, 2024.

Bibliography: pages 70-86.

Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant public health threat globally, impacting both human and Veterinary Medicine. This study aimed to comprehensively investigate the prevalence, antibiotic susceptibility, and molecular characteristics of MRSA isolates from humans, dogs, and cats in Egypt. A total of 561 swab samples were meticulously collected from clinical cases and apparently healthy animals, with an additional 30 MRSA isolates obtained from humans. Extensive phenotypic identification and antibiotic susceptibility testing uncovered alarming resistance rates among MRSA isolates, particularly notable against oxacillin, cefoxitin, penicillin, and norfloxacin. Notably, all MRSA isolates unequivocally harbored the mecA gene, indicating robust methicillin resistance. Furthermore, molecular analysis through PCR assays targeting mecA, mecC, spa, and nuc genes provided intricate insights into the genetic landscape of the isolates. Intriguingly, a subset of MRSA isolates exhibited partial deletion of the nuc gene, posing significant diagnostic challenges. Phylogenetic analysis unveiled a strikingly high genetic similarity among MRSA isolates from diverse species origins, hinting at potential interspecies transmission dynamics. Importantly, detailed examination of the MRSA isolates' origins revealed intriguing patterns: canine samples exhibited a prevalence of approximately 5.5%, with 13 positive MRSA cases, while feline samples yielded 8 MRSA isolates, resulting in a prevalence of 2.5%. Unfortunately, due to sample unavailability, the incidence among humans was not estimated in this study. These findings underscore the pivotal role of pets, particularly dogs and cats, as potential reservoirs for MRSA transmission within communities. This study focuses on the urgent need for enhanced surveillance and robust control measures to curtail the spread of MRSA, considering both human and animal health ramifications.This study investigates also the efficacy of Platelet-Rich Plasma (PRP) alone and in combination with ciprofloxacin ear drops in treating Methicillin-resistant Staphylococcus aureus (MRSA) infected otitis externa in dogs. Seven dogs with bilateral MRSA otitis externa were enrolled, receiving ciprofloxacin ear drops in one ear and PRP drops in the other, either alone or combined. Clinical, cytological, and microbiological evaluations were conducted at four time points over 15 days. Results showed that the combined treatment significantly reduced MRSA load, with higher clinical and cytological recovery rates compared to single treatments. PRP, known for its regenerative properties, enhanced the antimicrobial activity of ciprofloxacin, suggesting a synergistic effect. This combined approach holds promise for effectively treating MRSA-infected otitis externa in dogs, offering a potentially safer and more sustainable alternative to traditional antibiotic therapy.

ﻣﯿﻜﺮوﺑﺎت اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) ﺗﺸﻜﻞ ﺗﮭﺪﯾﺪًا ﻛﺒﯿ ًﺮا ﻟﻠﺼﺤﺔ اﻟﻌﺎﻣﺔ ﻋﻠﻰ اﻟﺼﻌﯿﺪﯾﻦ اﻟﻌﺎﻟﻤﻲ واﻟﻤﺤﻠﻲ، ﻣﻤﺎ ﯾﺆﺛﺮ ﻋﻠﻰ اﻟﻄﺐ اﻟﺒﺸﺮي واﻟﺒﯿﻄﺮي ﻋﻠﻰ ﺣﺪ ﺳﻮاء. ھﺬه اﻟﺪراﺳﺔ ﺗﮭﺪف إﻟﻰ اﺳﺘﻜﺸﺎف اﻧﺘﺸﺎر ﻣﯿﻜﺮوﺑﺎت اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA)، ودرﺟﺔ ﺣﺴﺎﺳﯿﺘﮭﺎ ﻟﻠﻤﻀﺎدات اﻟﺤﯿﻮﯾﺔ، واﻟﺴﻤﺎت اﻟﺠﺰﯾﺌﯿﺔ ﻟﮭﺬة اﻟﻌﺘﺮات اﻟﻤﻌﺰوﻟﺔ ﻣﻦ اﻟﺒﺸﺮ واﻟﻜﻼب واﻟﻘﻄﻂ ﻓﻲ ﻣﺼﺮ. ﺗﻢ ﺗﺠﻤﯿﻊ ﻋﺪد 561 ﻋﯿﻨﺔ ﻣﻦ اﻟﻘﻄﻂ واﻟﻜﻼب، ﺑﺎﻹﺿﺎﻓﺔ إﻟﻰ 30 ﻣﻌﺰوﻟﺔ اﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ ﻣﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) ﻣﻦ اﻟﺒﺸﺮ. ﻛﺸﻔﺖ اﻟﻔﺤﻮﺻﺎت اﻟﻈﺎھﺮﯾﺔ واﺧﺘﺒﺎرات ﺣﺴﺎﺳﯿﺔ اﻟﻤﻀﺎدات اﻟﺤﯿﻮﯾﺔ ﻋﻦ ارﺗﻔﺎع ﻣﻌﺪﻻت اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﻀﺎدات اﻟﺤﯿﻮﯾﺔ ﺑﯿﻦ ﻣﻌﺰوﻻت اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA)، ﺧﺎﺻﺔ ﺿﺪ اﻷوﻛﺴﺎﺳﯿﻠﯿﻦ، واﻟﺴﯿﻔﻮﻛﺴﯿﺘﯿﻦ، واﻟﺒﻨﯿﺴﯿﻠﯿﻦ، واﻟﻨﻮرﻓﻠﻮﻛﺴﺎﺳﯿﻦ. ﺑﺎﻹﺿﺎﻓﺔ إﻟﻰ ذﻟﻚ اﺛﺒﺖ اﺧﺘﺒﺎر ﺗﻔﺎﻋﻞ اﻟﺒﻠﻤﺮة اﻟﻤﺘﺴﻠﺴﻞ ان ﺟﻤﯿﻊ ﻣﻌﺰوﻻت اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) ﺗﺤﻤﻞ ﺟﯿﻦ ﻣﻚ أ mecA، ﻣﻤﺎ ﯾﺪل ﻋﻠﻰ ﻣﻘﺎوﻣﺔ ﻗﻮﯾﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ. ﻛﻤﺎ ﻛﺸﻒ اﻟﺘﺤﻠﯿﻞ اﻟﺠﺰﯾﺌﻲ ﻟﻠﻤﻌﺰوﻻت ﻋﻦ ﻣﻌﻠﻮﻣﺎت دﻗﯿﻘﺔ ﺣﻮل اﻟﺴﻤﺎت اﻟﺠﯿﻨﯿﺔ ﻟﻠﻤﻌﺰوﻻت ﻟﻠﻜﺸﻒ ﻋﻦ ﺟﯿﻨﺎت ﻣﺴﺘﮭﺪﻓﺔ mecA، وmecC، وspa، و.nuc وﻣﻦ اﻟﺠﺪﯾﺮ ﺑﺎﻟﺬﻛﺮ أن ﺑﻌﺾ اﻟﻤﻌﺰوﻻت أظﮭﺮت ﺣﺬﻓًﺎ ﺟﺰﺋﯿًﺎ ﻟﺠﯿﻦ ﻧﻚ nuc، ﻣﻤﺎ ﯾﺸﻜﻞ ﺗﺤﺪﯾﺎت ﺗﺸﺨﯿﺼﯿﺔ ﻛﺒﯿﺮة. وﻛﺸﻒ ﺗﺤﻠﯿﻞ اﻟﺘﺘﺎﺑﻊ اﻟﺠﯿﻨﻰ (اﻟﻔﯿﻠﻮﺟﯿﻨﻲ) ﻋﻦ ﺗﺸﺎﺑﮫ ﺟﯿﻨﻲ ﻣﻠﺤﻮظ ﺑﯿﻦ ﻣﻌﺰوﻻت اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) ﻣﻦ أﺻﻮل وأﻧﻮاع ﻣﺨﺘﻠﻔﺔ، ﻣﻤﺎ ﯾﺸﯿﺮ إﻟﻰ وﺟﻮد اﻧﺘﻘﺎل ﻣﺤﺘﻤﻞ ﺑﯿﻦ اﻷﻧﻮاع. اطﮭﺮت ﻧﺘﺎﺋﺞ اﻟﺪراﺳﺔ
اﻧﺘﺸﺎرا ﻣﯿﻜﺮوب اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوم ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) ﺑﯿﻦ اﻟﻜﻼب واﻟﻘﻄﻂ ، ﻣﻤﺎ ﯾﺒﺮز اﻟﺪور اﻟﻤﺤﺘﻤﻞ ﻟﻠﺤﯿﻮاﻧﺎت اﻷﻟﯿﻔﺔ ﻓﻲ اﻧﺘﻘﺎل ھﺬةه اﻟﻤﯿﻜﺮوﺑﺎت داﺧﻞ اﻟﻤﺠﺘﻤﻌﺎت. ﻟﺬا، ﯾﻌﺪ ﺗﻌﺰﯾﺰ اﻟﺮﺻﺪ واﺗﺨﺎذ اﺟﺮاءات ﻣﻜﺎﻓﺤﺔ ﻓﻌﺎﻟﺔ أﻣﺮا ﺿﺮورﯾًﺎ ﻻﺣﺘﻮاء اﻧﺘﺸﺎراﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) واﻟﺤﺪ ﻣﻦ آﺛﺎره ﻋﻠﻰ ﺻﺤﺔ اﻻﻧﺴﺎن واﻟﺤﯿﻮان.

ھﺪﻓﺖ ھﺬه اﻟﺪراﺳﺔ اﯾﻀﺎ اﻟﻰ ﺗﻘﯿﻢ ﻓﻌﺎﻟﯿﺔ اﻟﺒﻼزﻣﺎ اﻟﻐﻨﯿﺔ ﺑﺎﻟﺼﻔﺎﺋﺢ (PRP) ﺑﻤﻔﺮدھﺎ او ﻓﻲ ﻣﺰﯾﺞ ﻣﻊ ﻗﻄﺮات اﻷذن ﺳﯿﺒﺮوﻓﻠﻮﻛﺴﺎﺳﯿﻦ ﻓﻲ ﻋﻼج اﻟﺘﮭﺎب اﻷذن اﻟﺨﺎرﺟﯿﺔ اﻟﻤﺼﺎﺣﺐ ﻟﻌﺪوى ﺑﻜﺘﯿﺮﯾﺎ اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) ﻓﻲ اﻟﻜﻼب. ﺗﻢ اﺟﺮاء ﺗﺠﺮﺑﺔ ﻋﻠﻰ ﻋﺪد ﺳﺒﻊ ﻛﻼب ﻣﺼﺎﺑﺔ ﺑﺎﻟﺘﮭﺎب اﻷذن اﻟﺨﺎرﺟﯿﺔ اﻟﻤﺰدوج اﻟﺠﺎﻧﺐ ﻣﺼﺤﻮب ﺑﻌﺪوى اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA)، ﺣﯿﺚ ﺗﻠﻘﺖ ﻗﻄﺮات اﻷذن ﺳﯿﺒﺮوﻓﻠﻮﻛﺴﺎﺳﯿﻦ ﻓﻲ أﺣﺪ اﻷذﻧﯿﻦ وﻗﻄﺮات اﻟﺒﻼزﻣﺎ اﻟﻐﻨﯿﺔ ﺑﺎﻟﺼﻔﺎﺋﺢ PRP ﻓﻲ اﻷذن اﻷﺧﺮى، إﻣﺎ ﺑﻤﻔﺮدھﺎ أو ﻣﺠﺘﻤﻌﺔ. ﺗﻢ إﺟﺮاء ﺗﻘﯿﯿﻤﺎت ﺳﺮﯾﺮﯾﺔ وﺧﻠﻮﯾﺔ وﻣﯿﻜﺮوﺑﯿﻮﻟﻮﺟﯿﺔ ﻓﻲ أرﺑﻊ ﻧﻘﺎط زﻣﻨﯿﺔ ﻋﻠﻰ ﻣﺪى 15 ﯾﻮ ًﻣﺎ. اﺛﺒﺘﺖ اﻟﻨﺘﺎﺋﺞ ان اﻟﺒﻼزﻣﺎ اﻟﻐﻨﯿﺔ ﺑﺎﻟﺼﻔﺎﺋﺢ PRP اﻟﻤﻌﺮوﻓﺔ ﺑﺨﺼﺎﺋﺼﮭﺎ اﻟﺘﺠﺪدﯾﺔ، زادت ﻣﻦ اﻟﻨﺸﺎط اﻟﻤﻀﺎد ﻟﻠﻤﯿﻜﺮوﺑﺎت ﻟﺴﯿﺒﺮوﻓﻠﻮﻛﺴﺎﺳﯿﻦ، ﻣﻤﺎ ﯾﻮﺣﻲ ﺑﺘﺄﺛﯿﺮ ﺗﻌﺎوﻧﻲ. وﯾﻌﺪ ھﺬا اﻟﻨﮭﺞ وﺳﯿﻠﺔ ﻓﻌﺎﻟﺔ واﻋﺪة ﻟﻌﻼج ﺑﻜﺘﯿﺮﯾﺎ اﻻﺳﺘﺎﻓﯿﺎوﻛﻮﻛﺲ اورﯾﺲ اﻟﻤﻘﺎوﻣﺔ ﻟﻠﻤﯿﺜﯿﺴﯿﻠﯿﻦ (MRSA) اﻟﻤﺼﺎﺣﺒﺔ ﻻﻟﺘﮭﺎب اﻷذن اﻟﺨﺎرﺟﯿﺔ ﻓﻲ اﻟﻜﻼب، ﻣﻤﺎ ﯾﻘﺪم ﺑﺪﯾﻼً أﻛﺜﺮ أﻣﺎﻧًﺎ واﺳﺘﺪاﻣﺔ ﻋﻦ اﻟﻌﻼج ﺑﺎﻟﻤﻀﺎدات اﻟﺤﯿﻮﯾﺔ اﻟﺘﻘﻠﯿﺪﯾﺔ.

Issued also as CD

Text in English and abstract in Arabic & English.