3. Acinetobacter is a genus of Gram-negative
bacteria that has garnered increasing attention
due to its significance in microbiology and
healthcare. These bacteria are known for their
resilience and adaptability, often thriving in
diverse environments. Understanding the
various aspects of Acinetobacter is crucial for
addressing its impact on human health.
5. Acinetobacter belongs to the Moraxellaceae
family and encompasses numerous species,
with A. baumannii being the most
clinically relevant. Within this genus, each
species exhibits distinct characteristics and
behaviours, influencing their prevalence in
different environments.
9. Microscopically, Acinetobacter appears as
small, non-motile and coccobacillus-shaped
cells. Their cell structure is defined by a
Gram-negative outer membrane, which plays
a role in their resistance to various
environmental stresses.
11. While Acinetobacter is typically harmless in
natural environments, it can transform into an
opportunistic pathogen in healthcare settings.
It is notorious for causing a range of
infections, including pneumonia, bloodstream
infections, urinary tract infections and wound
infections, particularly in
immunocompromised individuals.
13. One of the defining features of
Acinetobacter is its remarkable resistance
to multiple antibiotics. This resistance is
attributed to mechanisms such as efflux
pumps, biofilm formation, and the
acquisition of resistance genes. The
emergence of multidrug-resistant strains
poses a significant challenge in clinical
settings.
15. In hospitals, Acinetobacter infections are a
growing concern, especially among intensive
care unit (ICU) patients. The ability of these
bacteria to survive on surfaces and medical
equipment contributes to their persistence in
healthcare environments. Acinetobacter
infections are associated with increased
morbidity and mortality rates.
16. Hospital Surfaces and Medical Equipment:
•Acinetobacter has the ability to survive on inanimate
surfaces, making contaminated hospital surfaces
and medical equipment potential sources of
infection.
•Reservoirs on surfaces such as bedrails,
countertops, and medical devices contribute to the
persistence of Acinetobacter in healthcare settings.
17. Person-to-Person Transmission:
•Person-to-person transmission, particularly in
crowded and high-risk settings like intensive care units
(ICUs), can occur through direct or indirect contact.
•Infected patients, healthcare workers, or
contaminated hands can serve as sources for the
spread of Acinetobacter.
18. Respiratory Equipment and Ventilators:
•Respiratory care equipment, including ventilators and
respiratory therapy devices, can become
contaminated with Acinetobacter.
•Patients on mechanical ventilation are at an
increased risk of respiratory infections, including
pneumonia caused by Acinetobacter.
19. Water Sources:
•Acinetobacter has been found in water sources within
healthcare facilities, including taps, sinks, and water
reservoirs.
•Contaminated water can serve as a source of
infection, particularly in patients with weakened
immune systems.
20. Wound Care and Catheters:
•Invasive medical procedures, such as wound care
and the use of catheters, pose a risk for
Acinetobacter infections.
•The ability of these bacteria to form biofilms on
medical devices enhances their persistence and
resistance to treatment.
21. Cross-Contamination in Food and Environmental
Services:
•Cross-contamination in hospital kitchens and
environmental services can contribute to the spread of
Acinetobacter.
•Strict hygiene practices in food preparation and
environmental cleaning are essential to prevent
contamination.
22. Colonization of Patients:
•Patients, especially those with compromised
immune systems, may carry Acinetobacter
asymptomatically.
•Colonized patients can serve as reservoirs, and the
risk of infection increases during hospitalization or
medical interventions.
24. Acinetobacter has a global distribution, and its
prevalence varies across regions. Outbreaks in
healthcare settings, often linked to
contaminated medical equipment, highlight the
need for stringent infection control measures.
Monitoring the epidemiology of Acinetobacter is
crucial for preventing and managing outbreaks.
26. Diagnostic methods include culturing samples,
molecular techniques and susceptibility testing
to determine antibiotic resistance patterns.
Rapid and precise identification is critical for
implementing appropriate therapeutic
strategies.
28. The management of Acinetobacter infections
is complicated by their resistance to multiple
antibiotics. Treatment options may include
combination therapy and the use of
antibiotics that retain efficacy against
resistant strains. Surveillance and infection
control practices are integral to preventing
the spread of these bacteria in healthcare
settings.
29. Antibiotic Therapy:
•Acinetobacter is notorious for its resistance to a
broad range of antibiotics, including commonly used
ones like penicillins, cephalosporins, and
carbapenems.
•Combination antibiotic therapy, using drugs such
as colistin, tigecycline, and sulbactam, may be
employed to enhance efficacy against multidrug-
resistant strains.
30. Combination Therapy:
•Combining different classes of antibiotics with distinct
mechanisms of action can help overcome resistance.
•Synergistic effects of multiple antibiotics may
enhance the overall effectiveness of the treatment.
31. •Colistin, a polymyxin antibiotic, is often
considered a last-resort option for treating
Acinetobacter infections.
•Polymyxins disrupt the bacterial cell membrane,
providing an alternative mechanism of action
against resistant strains.
COLISTIN
32. •Tigecycline, a glycylcycline antibiotic, is another
option for treating Acinetobacter infections.
•Its ability to overcome some resistance
mechanisms makes it valuable in the management
of certain cases.
TIGECYCLINE
34. Effectively preventing and controlling
Acinetobacter infections requires a
comprehensive and multi-faceted approach.
The implementation of stringent measures is
crucial in both healthcare and community
settings to minimize the spread of these
resilient bacteria.
35. • Hand Hygiene
• Patient isolation
• Personal Protective Equipment
• Regular cleaning & disinfection of patient
surroundings
• Judicious use of Antibiotics
• Water quality monitoring
• Reducing Moisture
• Regulatory oversight
37. Acinetobacter represents a significant
challenge in healthcare, given its ability to
cause opportunistic infections and its
resistance to multiple antibiotics. Continued
research, effective surveillance, and
stringent infection control measures are
essential for addressing the clinical impact
of Acinetobacter.
38. REFERENCES
1. World Health Organization (WHO). (2017). Guidelines for the prevention and control of
carbapenem-resistant Enterobacteriaceae, Acinetobacter baumannii and Pseudomonas
aeruginosa in health care facilities.
2. Bergogne-Bérézin, E., & Towner, K. J. (1996). Acinetobacter spp. as nosocomial
pathogens: microbiological, clinical, and epidemiological features. Clinical Microbiology
Reviews, 9(2), 148–165.
3. Peleg, A. Y., & Seifert, H. (2010). Acinetobacter baumannii: emergence of a successful
pathogen. Clinical Microbiology Reviews, 23(2), 538–582.
4. Doi, Y., Murray, G. L., Peleg, A. Y. (2015). Acinetobacter baumannii: Evolution of
Antimicrobial Resistance—Treatment Options. Seminars in Respiratory and Critical Care
Medicine, 36(1), 85–98.
5. Cisneros, J. M., Rodríguez-Baño, J., & Fernández-Cuenca, F. (2005). Risk-factors for the
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