Ochrobactrum anthropi is an emerging opportunistic pathogen that can potentially cause infections in humans, particularly in individuals with weakened immune systems or medical devices inserted into their bodies. The first documented case of O. anthropi infection dates back to 1980, when it was reported in a leukemia patient who developed septicemia and meningitis. Since then, over 100 cases of O. anthropi infection have been documented worldwide, primarily in Europe, North America, and Asia.
O. anthropi infections are often linked to using contaminated medical devices such as catheters, drainage tubes, dialysis machines, and infusion pumps. The bacterium can form biofilms on these devices, enhancing its resistance to disinfection procedures. Typically, O. anthropi infections are considered nosocomial, acquired within a hospital or healthcare facility. However, community-acquired infections have affected both healthy individuals and those with underlying medical conditions.
One notable challenge in managing O. anthropi infections is its resistance to multiple antibiotics, including penicillins, cephalosporins, and quinolones. Notably, O. anthropi shares a close genetic relationship with the Brucella species responsible for causing brucellosis—a zoonotic disease affecting animals and humans. However, O. anthropi does not cause brucellosis and does not produce positive results in Brucella-specific serological tests.
Classification and Structure:
Kingdom: Bacteria
Phylum: Pseudomonadota
Class: Alphaproteobacteria
Order: Hyphomicrobiales
Family: Brucellaceae
Genus:Ochrobactrum
Species:Ochrobactrum anthropic
Ochrobactrum anthropi is a gram-negative bacterium characterized by its rod-shaped morphology and motility facilitated by peritrichous flagella.When cultured on nutrient agar, it forms non-pigmented circular colonies, low convex, smooth, shining, and size approximately 1 μm diameter.The bacterium’s genome boasts a C+G content of 56.22% and a total size of 4.8 Mb, comprised of two distinct circular chromosomes and four plasmids.
The genome of Ochrobactrum anthropi includes four plasmids, each with distinct characteristics. They are small, circular DNA molecules that can carry various genetic elements and often play essential roles in bacterial physiology and adaptation.
pOAN03, pOAN02, & pOAN01: These plasmids exhibit the typical features and characteristics commonly associated with alphaproteobacterial plasmids. They likely contain known replication, partition, and conjugative systems essential for plasmid maintenance, distribution, and transfer among bacterial cells.
β-lactamase Genes:Ochrobactrum anthropi harbors a distinctive β-lactamase gene variant known as blaOCH. This gene belongs to the AmpC-like class C β-lactamases. In approximately 76% of O. anthropi genomes, blaOCH confers resistance to a wide range of β-lactam antibiotics, including penicillins and cephalosporins. This genetic feature renders these antibiotics ineffective against the bacterium, contributing to its ability to persist in clinical settings.
Role of Lipopolysaccharides (LPS): Lipopolysaccharides (LPS) are intricate molecules found in the outer layer of bacterial cell walls. LPS serves crucial functions in bacterial survival, adhesion, and resistance to host defenses by comprising a core oligosaccharide, lipid A, and an O-antigen polysaccharide. Simultaneously, they can provoke inflammatory responses and, in severe cases, septic shock in the host. The presence of LPS contributes to O. anthropi‘s pathogenic potential and interaction with the host immune system.
Hemolysins:O. anthropi can produce hemolysins from the family of RTX (repeats in toxin). These toxins can lyse red blood cells, releasing hemoglobin. Hemolysins play a multifaceted role, aiding the bacterium in acquiring iron from hemoglobin, causing tissue damage, and triggering inflammatory responses within the host. This array of virulence factors underscores O. anthropi‘s adaptability and pathogenicity.
Notable O. anthropi Strains: Among the various strains of O. anthropi, two notable examples include CIP 14970, the type strain initially isolated from a human blood culture in 1980, and ATCC 49188, a clinical strain derived from a patient with endocarditis in 1986. These strains have contributed significantly to our understanding of O. anthropi‘s clinical implications and mechanisms of infection.
The pathogenesis of Ochrobactrum anthropi in humans remains incompletely understood, but several proposed mechanisms shed light on its potential virulence. O. anthropi has been found to adhere to and invade human epithelial cells lining various body tissues, including the respiratory tract, urinary tract, and blood vessels. This interaction can trigger tissue damage and provoke inflammation, contributing to the bacterium’s pathogenicity.
One prominent feature of O. anthropi is its ability to form resilient biofilms on medical devices like catheters, drainage tubes, dialysis machines, and infusion pumps. These biofilms act as protective shields, rendering the bacterium resistant to disinfection and antibiotics. Consequently, this resilience can lead to persistent infections, resulting in severe complications such as bacteremia, endocarditis, or septic shock.
O. anthropi possesses various virulence factors, including lipopolysaccharides, siderophores, proteases, and hemolysins. These virulence factors can modulate the host’s immune response and inflict cellular damage, further contributing to its pathogenicity.
Another intriguing aspect of O. anthropi‘s pathogenesis is its potential to evade the host immune system. It shares a genetic resemblance with Brucella species, which cause brucellosis—a zoonotic disease. O. anthropi can mimic Brucella, avoiding recognition by Brucella-specific antibodies and phagocytes. Moreover, it can survive intracellularly within macrophages, adding to its immune evasion strategies.
While O. anthropi is often associated with community-acquired infections, it primarily affects critically ill or immunocompromised individuals with and without indwelling catheters. Despite its capacity to cause clinically significant infections, O. anthropi is considered to have relatively low virulence.
The human host defense mechanisms against Ochrobactrumanthropi have yet to be extensively studied or well-documented in the available literature. This lack of information suggests that O. anthropi may not be a standard or highly virulent pathogen in healthy individuals with robust immune systems. Therefore, detailed investigations into host defense responses may have yet to be a research priority.
Ochrobactrum anthropi infections can manifest in various clinical forms, each posing distinct challenges for both patients and healthcare providers. One concerning manifestation is bacteremia, where the bacterium enters the bloodstream.
This condition can escalate into septic shock, a life-threatening state characterized by critically low blood pressure, organ dysfunction, and a heightened mortality risk. O. anthropi bacteremia is frequently associated with catheter-related bloodstream infections, and its management is complicated by the bacterium’s antibiotic resistance, making effective treatment more complex.
Another clinical presentation linked to O. anthropi infection is pneumonia, an inflammatory condition affecting the lungs due to infection. Patients with O. anthropi pneumonia may exhibit cough, fever, chest pain, and respiratory distress symptoms. Although O. anthropi pneumonia is relatively uncommon, it has been observed in individuals with pre-existing chronic lung conditions or compromised immune systems.
Endocarditis represents a rarer but severe form of O. anthropi infection involving the infection of the heart’s inner lining or valves. This condition can result in heart damage and critical complications, including heart failure, stroke, or embolism. Instances of O.
anthropi endocarditis have been reported in patients with congenital heart defects, those with prosthetic heart valves, or individuals engaged in intravenous drug use. Managing and treating O. anthropi-induced endocarditis necessitates meticulous medical care and intervention due to its potential for severe consequences.
Diagnosing Ochrobactrum anthropi infections involves a comprehensive approach with several tests and considerations:
Specimen Collection and Processing: To initiate the diagnostic process, clinical specimens are collected from various sources, including blood, wound swabs, urine, aspiration fluids, nasal & nasopharyngeal swabs, aural swabs, stool, CSF, and central line catheters. To prevent contamination, it is crucial to process these samples promptly, within 30 minutes to 1 hour.
Culture test: Clinical samples are subjected to direct Gram staining, which allows for the visualization of slender, gram-negative bacilli. Specimens suspected of O. anthropi infection are cultured on appropriate agar media, such as 5% sheep blood agar, MacConkey agar, and chocolate agar. O. anthropi colonies typically appear small, approximately 1mm in diameter, and display characteristic features: circular, smooth, low convex, shining. Notably, on MacConkey agar, they often exhibit a mucoid appearance and do not ferment lactose, distinguishing them from other bacteria.
Biochemical Tests: Several key tests are employed to distinguish O. anthropi from related organisms:
Urea Hydrolysis:O. anthropi is positive for urea hydrolysis.
Esculin Hydrolysis:O. anthropi is unable to hydrolyze esculin.
ONPG Test:O. anthropi exhibits a negative ONPG (ortho-nitrophenyl-β-galactoside) test.
Confirmation and Differentiation: By its genetic similarity to Brucella species, O. anthropi may be misidentified, especially by automated systems like API 20NE, which might classify it as Brucella due to their close relation. Therefore, confirming the diagnosis is essential. This can be achieved through negative serum Brucella species antibodies, especially in cases where patients present with severe infections caused by O. anthropi bacteremia without a clear primary focus of infection and when standard treatments are ineffective.
Misidentification Concerns: There have been reports of misidentification, particularly of O. anthropi as Brucellosis infection, due to the genetic overlap between these two organisms. This misidentification can lead to cross-reactivity in tests such as 16S ribosomal RNA sequence signatures and Western blot.
Advanced Diagnostic Tools: To overcome the challenges posed by the close phylogenetic relationship between O. anthropi and Brucella species, advanced diagnostic tools like automated culture systems such as VITEK-2 and MALDI-TOF assay are recommended for accurate identification. These systems are better equipped to differentiate between O. anthropi and Brucella.
Healthcare providers should adhere to standard precautions, including proper hand hygiene, personal protective equipment (PPE), gloves and gowns, and respiratory hygiene.
Sharps and medical waste should be handled safely and disposed of following recommended guidelines to prevent accidental exposure. Regular cleaning and disinfection of patient care areas and equipment are essential to reduce the risk of O. anthropi transmission.
If an outbreak is suspected or confirmed, implement containment measures such as isolating infected patients, tracing contacts, cohorting staff and patients, and enhancing infection control protocols.
Ochrobactrum anthropi is an emerging opportunistic pathogen that can potentially cause infections in humans, particularly in individuals with weakened immune systems or medical devices inserted into their bodies. The first documented case of O. anthropi infection dates back to 1980, when it was reported in a leukemia patient who developed septicemia and meningitis. Since then, over 100 cases of O. anthropi infection have been documented worldwide, primarily in Europe, North America, and Asia.
O. anthropi infections are often linked to using contaminated medical devices such as catheters, drainage tubes, dialysis machines, and infusion pumps. The bacterium can form biofilms on these devices, enhancing its resistance to disinfection procedures. Typically, O. anthropi infections are considered nosocomial, acquired within a hospital or healthcare facility. However, community-acquired infections have affected both healthy individuals and those with underlying medical conditions.
One notable challenge in managing O. anthropi infections is its resistance to multiple antibiotics, including penicillins, cephalosporins, and quinolones. Notably, O. anthropi shares a close genetic relationship with the Brucella species responsible for causing brucellosis—a zoonotic disease affecting animals and humans. However, O. anthropi does not cause brucellosis and does not produce positive results in Brucella-specific serological tests.
Classification and Structure:
Kingdom: Bacteria
Phylum: Pseudomonadota
Class: Alphaproteobacteria
Order: Hyphomicrobiales
Family: Brucellaceae
Genus:Ochrobactrum
Species:Ochrobactrum anthropic
Ochrobactrum anthropi is a gram-negative bacterium characterized by its rod-shaped morphology and motility facilitated by peritrichous flagella.When cultured on nutrient agar, it forms non-pigmented circular colonies, low convex, smooth, shining, and size approximately 1 μm diameter.The bacterium’s genome boasts a C+G content of 56.22% and a total size of 4.8 Mb, comprised of two distinct circular chromosomes and four plasmids.
The genome of Ochrobactrum anthropi includes four plasmids, each with distinct characteristics. They are small, circular DNA molecules that can carry various genetic elements and often play essential roles in bacterial physiology and adaptation.
pOAN03, pOAN02, & pOAN01: These plasmids exhibit the typical features and characteristics commonly associated with alphaproteobacterial plasmids. They likely contain known replication, partition, and conjugative systems essential for plasmid maintenance, distribution, and transfer among bacterial cells.
β-lactamase Genes:Ochrobactrum anthropi harbors a distinctive β-lactamase gene variant known as blaOCH. This gene belongs to the AmpC-like class C β-lactamases. In approximately 76% of O. anthropi genomes, blaOCH confers resistance to a wide range of β-lactam antibiotics, including penicillins and cephalosporins. This genetic feature renders these antibiotics ineffective against the bacterium, contributing to its ability to persist in clinical settings.
Role of Lipopolysaccharides (LPS): Lipopolysaccharides (LPS) are intricate molecules found in the outer layer of bacterial cell walls. LPS serves crucial functions in bacterial survival, adhesion, and resistance to host defenses by comprising a core oligosaccharide, lipid A, and an O-antigen polysaccharide. Simultaneously, they can provoke inflammatory responses and, in severe cases, septic shock in the host. The presence of LPS contributes to O. anthropi‘s pathogenic potential and interaction with the host immune system.
Hemolysins:O. anthropi can produce hemolysins from the family of RTX (repeats in toxin). These toxins can lyse red blood cells, releasing hemoglobin. Hemolysins play a multifaceted role, aiding the bacterium in acquiring iron from hemoglobin, causing tissue damage, and triggering inflammatory responses within the host. This array of virulence factors underscores O. anthropi‘s adaptability and pathogenicity.
Notable O. anthropi Strains: Among the various strains of O. anthropi, two notable examples include CIP 14970, the type strain initially isolated from a human blood culture in 1980, and ATCC 49188, a clinical strain derived from a patient with endocarditis in 1986. These strains have contributed significantly to our understanding of O. anthropi‘s clinical implications and mechanisms of infection.
The pathogenesis of Ochrobactrum anthropi in humans remains incompletely understood, but several proposed mechanisms shed light on its potential virulence. O. anthropi has been found to adhere to and invade human epithelial cells lining various body tissues, including the respiratory tract, urinary tract, and blood vessels. This interaction can trigger tissue damage and provoke inflammation, contributing to the bacterium’s pathogenicity.
One prominent feature of O. anthropi is its ability to form resilient biofilms on medical devices like catheters, drainage tubes, dialysis machines, and infusion pumps. These biofilms act as protective shields, rendering the bacterium resistant to disinfection and antibiotics. Consequently, this resilience can lead to persistent infections, resulting in severe complications such as bacteremia, endocarditis, or septic shock.
O. anthropi possesses various virulence factors, including lipopolysaccharides, siderophores, proteases, and hemolysins. These virulence factors can modulate the host’s immune response and inflict cellular damage, further contributing to its pathogenicity.
Another intriguing aspect of O. anthropi‘s pathogenesis is its potential to evade the host immune system. It shares a genetic resemblance with Brucella species, which cause brucellosis—a zoonotic disease. O. anthropi can mimic Brucella, avoiding recognition by Brucella-specific antibodies and phagocytes. Moreover, it can survive intracellularly within macrophages, adding to its immune evasion strategies.
While O. anthropi is often associated with community-acquired infections, it primarily affects critically ill or immunocompromised individuals with and without indwelling catheters. Despite its capacity to cause clinically significant infections, O. anthropi is considered to have relatively low virulence.
The human host defense mechanisms against Ochrobactrumanthropi have yet to be extensively studied or well-documented in the available literature. This lack of information suggests that O. anthropi may not be a standard or highly virulent pathogen in healthy individuals with robust immune systems. Therefore, detailed investigations into host defense responses may have yet to be a research priority.
Ochrobactrum anthropi infections can manifest in various clinical forms, each posing distinct challenges for both patients and healthcare providers. One concerning manifestation is bacteremia, where the bacterium enters the bloodstream.
This condition can escalate into septic shock, a life-threatening state characterized by critically low blood pressure, organ dysfunction, and a heightened mortality risk. O. anthropi bacteremia is frequently associated with catheter-related bloodstream infections, and its management is complicated by the bacterium’s antibiotic resistance, making effective treatment more complex.
Another clinical presentation linked to O. anthropi infection is pneumonia, an inflammatory condition affecting the lungs due to infection. Patients with O. anthropi pneumonia may exhibit cough, fever, chest pain, and respiratory distress symptoms. Although O. anthropi pneumonia is relatively uncommon, it has been observed in individuals with pre-existing chronic lung conditions or compromised immune systems.
Endocarditis represents a rarer but severe form of O. anthropi infection involving the infection of the heart’s inner lining or valves. This condition can result in heart damage and critical complications, including heart failure, stroke, or embolism. Instances of O.
anthropi endocarditis have been reported in patients with congenital heart defects, those with prosthetic heart valves, or individuals engaged in intravenous drug use. Managing and treating O. anthropi-induced endocarditis necessitates meticulous medical care and intervention due to its potential for severe consequences.
Diagnosing Ochrobactrum anthropi infections involves a comprehensive approach with several tests and considerations:
Specimen Collection and Processing: To initiate the diagnostic process, clinical specimens are collected from various sources, including blood, wound swabs, urine, aspiration fluids, nasal & nasopharyngeal swabs, aural swabs, stool, CSF, and central line catheters. To prevent contamination, it is crucial to process these samples promptly, within 30 minutes to 1 hour.
Culture test: Clinical samples are subjected to direct Gram staining, which allows for the visualization of slender, gram-negative bacilli. Specimens suspected of O. anthropi infection are cultured on appropriate agar media, such as 5% sheep blood agar, MacConkey agar, and chocolate agar. O. anthropi colonies typically appear small, approximately 1mm in diameter, and display characteristic features: circular, smooth, low convex, shining. Notably, on MacConkey agar, they often exhibit a mucoid appearance and do not ferment lactose, distinguishing them from other bacteria.
Biochemical Tests: Several key tests are employed to distinguish O. anthropi from related organisms:
Urea Hydrolysis:O. anthropi is positive for urea hydrolysis.
Esculin Hydrolysis:O. anthropi is unable to hydrolyze esculin.
ONPG Test:O. anthropi exhibits a negative ONPG (ortho-nitrophenyl-β-galactoside) test.
Confirmation and Differentiation: By its genetic similarity to Brucella species, O. anthropi may be misidentified, especially by automated systems like API 20NE, which might classify it as Brucella due to their close relation. Therefore, confirming the diagnosis is essential. This can be achieved through negative serum Brucella species antibodies, especially in cases where patients present with severe infections caused by O. anthropi bacteremia without a clear primary focus of infection and when standard treatments are ineffective.
Misidentification Concerns: There have been reports of misidentification, particularly of O. anthropi as Brucellosis infection, due to the genetic overlap between these two organisms. This misidentification can lead to cross-reactivity in tests such as 16S ribosomal RNA sequence signatures and Western blot.
Advanced Diagnostic Tools: To overcome the challenges posed by the close phylogenetic relationship between O. anthropi and Brucella species, advanced diagnostic tools like automated culture systems such as VITEK-2 and MALDI-TOF assay are recommended for accurate identification. These systems are better equipped to differentiate between O. anthropi and Brucella.
Healthcare providers should adhere to standard precautions, including proper hand hygiene, personal protective equipment (PPE), gloves and gowns, and respiratory hygiene.
Sharps and medical waste should be handled safely and disposed of following recommended guidelines to prevent accidental exposure. Regular cleaning and disinfection of patient care areas and equipment are essential to reduce the risk of O. anthropi transmission.
If an outbreak is suspected or confirmed, implement containment measures such as isolating infected patients, tracing contacts, cohorting staff and patients, and enhancing infection control protocols.
Ochrobactrum anthropi is an emerging opportunistic pathogen that can potentially cause infections in humans, particularly in individuals with weakened immune systems or medical devices inserted into their bodies. The first documented case of O. anthropi infection dates back to 1980, when it was reported in a leukemia patient who developed septicemia and meningitis. Since then, over 100 cases of O. anthropi infection have been documented worldwide, primarily in Europe, North America, and Asia.
O. anthropi infections are often linked to using contaminated medical devices such as catheters, drainage tubes, dialysis machines, and infusion pumps. The bacterium can form biofilms on these devices, enhancing its resistance to disinfection procedures. Typically, O. anthropi infections are considered nosocomial, acquired within a hospital or healthcare facility. However, community-acquired infections have affected both healthy individuals and those with underlying medical conditions.
One notable challenge in managing O. anthropi infections is its resistance to multiple antibiotics, including penicillins, cephalosporins, and quinolones. Notably, O. anthropi shares a close genetic relationship with the Brucella species responsible for causing brucellosis—a zoonotic disease affecting animals and humans. However, O. anthropi does not cause brucellosis and does not produce positive results in Brucella-specific serological tests.
Classification and Structure:
Kingdom: Bacteria
Phylum: Pseudomonadota
Class: Alphaproteobacteria
Order: Hyphomicrobiales
Family: Brucellaceae
Genus:Ochrobactrum
Species:Ochrobactrum anthropic
Ochrobactrum anthropi is a gram-negative bacterium characterized by its rod-shaped morphology and motility facilitated by peritrichous flagella.When cultured on nutrient agar, it forms non-pigmented circular colonies, low convex, smooth, shining, and size approximately 1 μm diameter.The bacterium’s genome boasts a C+G content of 56.22% and a total size of 4.8 Mb, comprised of two distinct circular chromosomes and four plasmids.
The genome of Ochrobactrum anthropi includes four plasmids, each with distinct characteristics. They are small, circular DNA molecules that can carry various genetic elements and often play essential roles in bacterial physiology and adaptation.
pOAN03, pOAN02, & pOAN01: These plasmids exhibit the typical features and characteristics commonly associated with alphaproteobacterial plasmids. They likely contain known replication, partition, and conjugative systems essential for plasmid maintenance, distribution, and transfer among bacterial cells.
β-lactamase Genes:Ochrobactrum anthropi harbors a distinctive β-lactamase gene variant known as blaOCH. This gene belongs to the AmpC-like class C β-lactamases. In approximately 76% of O. anthropi genomes, blaOCH confers resistance to a wide range of β-lactam antibiotics, including penicillins and cephalosporins. This genetic feature renders these antibiotics ineffective against the bacterium, contributing to its ability to persist in clinical settings.
Role of Lipopolysaccharides (LPS): Lipopolysaccharides (LPS) are intricate molecules found in the outer layer of bacterial cell walls. LPS serves crucial functions in bacterial survival, adhesion, and resistance to host defenses by comprising a core oligosaccharide, lipid A, and an O-antigen polysaccharide. Simultaneously, they can provoke inflammatory responses and, in severe cases, septic shock in the host. The presence of LPS contributes to O. anthropi‘s pathogenic potential and interaction with the host immune system.
Hemolysins:O. anthropi can produce hemolysins from the family of RTX (repeats in toxin). These toxins can lyse red blood cells, releasing hemoglobin. Hemolysins play a multifaceted role, aiding the bacterium in acquiring iron from hemoglobin, causing tissue damage, and triggering inflammatory responses within the host. This array of virulence factors underscores O. anthropi‘s adaptability and pathogenicity.
Notable O. anthropi Strains: Among the various strains of O. anthropi, two notable examples include CIP 14970, the type strain initially isolated from a human blood culture in 1980, and ATCC 49188, a clinical strain derived from a patient with endocarditis in 1986. These strains have contributed significantly to our understanding of O. anthropi‘s clinical implications and mechanisms of infection.
The pathogenesis of Ochrobactrum anthropi in humans remains incompletely understood, but several proposed mechanisms shed light on its potential virulence. O. anthropi has been found to adhere to and invade human epithelial cells lining various body tissues, including the respiratory tract, urinary tract, and blood vessels. This interaction can trigger tissue damage and provoke inflammation, contributing to the bacterium’s pathogenicity.
One prominent feature of O. anthropi is its ability to form resilient biofilms on medical devices like catheters, drainage tubes, dialysis machines, and infusion pumps. These biofilms act as protective shields, rendering the bacterium resistant to disinfection and antibiotics. Consequently, this resilience can lead to persistent infections, resulting in severe complications such as bacteremia, endocarditis, or septic shock.
O. anthropi possesses various virulence factors, including lipopolysaccharides, siderophores, proteases, and hemolysins. These virulence factors can modulate the host’s immune response and inflict cellular damage, further contributing to its pathogenicity.
Another intriguing aspect of O. anthropi‘s pathogenesis is its potential to evade the host immune system. It shares a genetic resemblance with Brucella species, which cause brucellosis—a zoonotic disease. O. anthropi can mimic Brucella, avoiding recognition by Brucella-specific antibodies and phagocytes. Moreover, it can survive intracellularly within macrophages, adding to its immune evasion strategies.
While O. anthropi is often associated with community-acquired infections, it primarily affects critically ill or immunocompromised individuals with and without indwelling catheters. Despite its capacity to cause clinically significant infections, O. anthropi is considered to have relatively low virulence.
The human host defense mechanisms against Ochrobactrumanthropi have yet to be extensively studied or well-documented in the available literature. This lack of information suggests that O. anthropi may not be a standard or highly virulent pathogen in healthy individuals with robust immune systems. Therefore, detailed investigations into host defense responses may have yet to be a research priority.
Ochrobactrum anthropi infections can manifest in various clinical forms, each posing distinct challenges for both patients and healthcare providers. One concerning manifestation is bacteremia, where the bacterium enters the bloodstream.
This condition can escalate into septic shock, a life-threatening state characterized by critically low blood pressure, organ dysfunction, and a heightened mortality risk. O. anthropi bacteremia is frequently associated with catheter-related bloodstream infections, and its management is complicated by the bacterium’s antibiotic resistance, making effective treatment more complex.
Another clinical presentation linked to O. anthropi infection is pneumonia, an inflammatory condition affecting the lungs due to infection. Patients with O. anthropi pneumonia may exhibit cough, fever, chest pain, and respiratory distress symptoms. Although O. anthropi pneumonia is relatively uncommon, it has been observed in individuals with pre-existing chronic lung conditions or compromised immune systems.
Endocarditis represents a rarer but severe form of O. anthropi infection involving the infection of the heart’s inner lining or valves. This condition can result in heart damage and critical complications, including heart failure, stroke, or embolism. Instances of O.
anthropi endocarditis have been reported in patients with congenital heart defects, those with prosthetic heart valves, or individuals engaged in intravenous drug use. Managing and treating O. anthropi-induced endocarditis necessitates meticulous medical care and intervention due to its potential for severe consequences.
Diagnosing Ochrobactrum anthropi infections involves a comprehensive approach with several tests and considerations:
Specimen Collection and Processing: To initiate the diagnostic process, clinical specimens are collected from various sources, including blood, wound swabs, urine, aspiration fluids, nasal & nasopharyngeal swabs, aural swabs, stool, CSF, and central line catheters. To prevent contamination, it is crucial to process these samples promptly, within 30 minutes to 1 hour.
Culture test: Clinical samples are subjected to direct Gram staining, which allows for the visualization of slender, gram-negative bacilli. Specimens suspected of O. anthropi infection are cultured on appropriate agar media, such as 5% sheep blood agar, MacConkey agar, and chocolate agar. O. anthropi colonies typically appear small, approximately 1mm in diameter, and display characteristic features: circular, smooth, low convex, shining. Notably, on MacConkey agar, they often exhibit a mucoid appearance and do not ferment lactose, distinguishing them from other bacteria.
Biochemical Tests: Several key tests are employed to distinguish O. anthropi from related organisms:
Urea Hydrolysis:O. anthropi is positive for urea hydrolysis.
Esculin Hydrolysis:O. anthropi is unable to hydrolyze esculin.
ONPG Test:O. anthropi exhibits a negative ONPG (ortho-nitrophenyl-β-galactoside) test.
Confirmation and Differentiation: By its genetic similarity to Brucella species, O. anthropi may be misidentified, especially by automated systems like API 20NE, which might classify it as Brucella due to their close relation. Therefore, confirming the diagnosis is essential. This can be achieved through negative serum Brucella species antibodies, especially in cases where patients present with severe infections caused by O. anthropi bacteremia without a clear primary focus of infection and when standard treatments are ineffective.
Misidentification Concerns: There have been reports of misidentification, particularly of O. anthropi as Brucellosis infection, due to the genetic overlap between these two organisms. This misidentification can lead to cross-reactivity in tests such as 16S ribosomal RNA sequence signatures and Western blot.
Advanced Diagnostic Tools: To overcome the challenges posed by the close phylogenetic relationship between O. anthropi and Brucella species, advanced diagnostic tools like automated culture systems such as VITEK-2 and MALDI-TOF assay are recommended for accurate identification. These systems are better equipped to differentiate between O. anthropi and Brucella.
Healthcare providers should adhere to standard precautions, including proper hand hygiene, personal protective equipment (PPE), gloves and gowns, and respiratory hygiene.
Sharps and medical waste should be handled safely and disposed of following recommended guidelines to prevent accidental exposure. Regular cleaning and disinfection of patient care areas and equipment are essential to reduce the risk of O. anthropi transmission.
If an outbreak is suspected or confirmed, implement containment measures such as isolating infected patients, tracing contacts, cohorting staff and patients, and enhancing infection control protocols.
Both our subscription plans include Free CME/CPD AMA PRA Category 1 credits.
Digital Certificate PDF
On course completion, you will receive a full-sized presentation quality digital certificate.
medtigo Simulation
A dynamic medical simulation platform designed to train healthcare professionals and students to effectively run code situations through an immersive hands-on experience in a live, interactive 3D environment.
medtigo Points
medtigo points is our unique point redemption system created to award users for interacting on our site. These points can be redeemed for special discounts on the medtigo marketplace as well as towards the membership cost itself.
Community Forum post/reply = 5 points
*Redemption of points can occur only through the medtigo marketplace, courses, or simulation system. Money will not be credited to your bank account. 10 points = $1.
All Your Certificates in One Place
When you have your licenses, certificates and CMEs in one place, it's easier to track your career growth. You can easily share these with hospitals as well, using your medtigo app.
