Chronic granulomatous disease of childhood and Chromobacterium violaceum infections in the southeastern United States

Chemokine expression profile of an innate granuloma

Granulomas are defined by the presence of organized layers of immune cells that include macrophages. Granulomas are often characterized as a way for the immune system to contain an infection and prevent its dissemination. We recently established a mouse infection model where Chromobacterium violaceum induces the innate immune system to form granulomas in the liver. This response successfully eradicates the bacteria and returns the liver to homeostasis. Here, we sought to characterize the chemokines involved in directing immune cells to form the distinct layers of a granuloma. We use spatial transcriptomics to investigate the spatial and temporal expression of all CC and CXC chemokines and their receptors within this granuloma response. The expression profiles change dynamically over space and time as the granuloma matures and then resolves. To investigate the importance of monocyte-derived macrophages in this immune response, we studied the role of CCR2 during C. violaceum infection. Ccr2 -/- mice had negligible numbers of macrophages, but large numbers of neutrophils, in the C. violaceum-infected lesions. In addition, lesions had abnormal architecture resulting in loss of bacterial containment. Without CCR2, bacteria disseminated and the mice succumbed to the infection. This indicates that macrophages are critical to form a successful innate granuloma in response to C. violaceum.

Chromobacterium violaceum in a U.S. Marine: A Case Report

Chromobacterium violaceum is associated with severe sepsis leading to cutaneous and visceral organ abscesses, with mortality rates up to 73%. Around 200 cases of C. violaceum infection have been reported globally. We report a case of a 27-year-old female U.S. Marine recruit who presented with fever, chills, myalgias, arthralgias, headache, and nodules on her extremities. Physical examination revealed multiple small skin abscesses on her extremities. Abdominal imaging with contrast revealed large liver abscesses requiring drainage. Both blood and wound cultures grew C. violaceum. The patient was successfully treated with meropenem and ciprofloxacin. At 3 months, symptoms had resolved, and labs and imaging were normal. Though rare, C. violaceum infection rates are increasing. Severe infection develops rapidly and invasive disease is not uncommon. Early detection and appropriate antibiotic treatment are key in preventing mortality.

Validation of the Intermolecular Disulfide Bond in Caspase-2

Caspases are a family of proteins involved in cell death. Although several caspase members have been well characterized, caspase-2 remains enigmatic. Caspase-2 has been implicated in several phenotypes, but there has been no consensus in the field about its upstream activating signals or its downstream protein targets. In addition, the unique ability of caspase-2 to form a disulfide-bonded dimer has not been studied in depth. Herein, we investigate the disulfide bond in the context of inducible dimerization, showing that disulfide bond formation is dimerization dependent. We also explore and review several stimuli published in the caspase-2 field, test ferroptosis-inducing stimuli, and study in vivo infection models. We hypothesize that the disulfide bond will ultimately prove to be essential for the evolved function of caspase-2. Proving this will require the discovery of cell death phenotypes where caspase-2 is definitively essential.

An innate granuloma eradicates an environmental pathogen using Gsdmd and Nos2

Granulomas often form around pathogens that cause chronic infections. Here, we discover an innate granuloma model in mice with an environmental bacterium called Chromobacterium violaceum. Granuloma formation not only successfully walls off, but also clears, the infection. The infected lesion can arise from a single bacterium that replicates despite the presence of a neutrophil swarm. Bacterial replication ceases when macrophages organize around the infection and form a granuloma. This granuloma response is accomplished independently of adaptive immunity that is typically required to organize granulomas. The C. violaceum-induced granuloma requires at least two separate defense pathways, gasdermin D and iNOS, to maintain the integrity of the granuloma architecture. This innate granuloma successfully eradicates C. violaceum infection. Therefore, this C. violaceum-induced granuloma model demonstrates that innate immune cells successfully organize a granuloma and thereby resolve infection by an environmental pathogen.

Pyroptosis in defense against intracellular bacteria

Pathogenic microbes invade the human body and trigger a host immune response to defend against the infection. In response, host-adapted pathogens employ numerous virulence strategies to overcome host defense mechanisms. As a result, the interaction between the host and pathogen is a dynamic process that shapes the evolution of the host's immune response. Among the immune responses against intracellular bacteria, pyroptosis, a lytic form of cell death, is a crucial mechanism that eliminates replicative niches for intracellular pathogens and modulates the immune system by releasing danger signals. This review focuses on the role of pyroptosis in combating intracellular bacterial infection. We examine the cell type specific roles of pyroptosis in neutrophils and intestinal epithelial cells. We discuss the regulatory mechanisms of pyroptosis, including its modulation by autophagy and interferon-inducible GTPases. Furthermore, we highlight that while host-adapted pathogens can often subvert pyroptosis, environmental microbes are effectively eliminated by pyroptosis.

An innate granuloma eradicates an environmental pathogen using Gsdmd and Nos2

Granulomas often form around pathogens that cause chronic infections. Here, we discover a novel granuloma model in mice. Chromobacterium violaceum is an environmental bacterium that stimulates granuloma formation that not only successfully walls off but also clears the infection. The infected lesion can arise from a single bacterium that replicates in the presence of a neutrophil swarm. Bacterial replication ceases when macrophages organize around the infection and form a granuloma. This granuloma response is accomplished independently of adaptive immunity that is typically required to organize granulomas. The C. violaceum -induced granuloma requires at least two separate defense pathways, gasdermin D and iNOS, to maintain the integrity of the granuloma architecture. These innate granulomas successfully eradicate C. violaceum infection. Therefore, this new C. violaceum -induced granuloma model demonstrates that innate immune cells successfully organize a granuloma and thereby eradicate infection by an environmental pathogen.

Chromobacterium violaceum: A Review of an Unexpected Scourge

Chromobacterium violaceum is a common environmental bacterium that rarely causes disease in humans but has a high fatality rate if it does. Due to the rarity of the cases, clinicians are often unaware of the rapid progression of C. violaceum infection and its unexpected antibiotic resistance pattern, which contribute to the failure of patient management. Our review provides the clinical characteristics, possible sources of exposure, and comorbidities and determines factors associated with survival. We gathered information on 132 cases of C. violaceum causing disease in humans published between 1953 and 2020. Patients were predominantly male with a median age of 17.5, interquartile range (IQR) of 5.0-40.0 years, and a third of them were known to have immune deficiencies or comorbidities. Portals of entry were mainly through a wound in the leg and feet (28.0%), the torso (8.5%), or hands and arms (6.8%). It is not uncommon to acquire infection through unintended contact with contaminated water or dust through the mouth or inhalation. The median incubation period is 4.0 days (IQR 2.0-8.0 days) with a duration of clinical course of 17.5 days (IQR 8.0-30.8 days). The high rate of positive blood cultures (56.1%) and abscesses in internal organs (36.4%) shows the significant severity of this disease. Sepsis and Bacteremia were related to mortality with a risk ratio (RR) of 5.20 (95% CI, 0.831-32.58) and 2.14 (95% CI, 1.05-4.36), respectively. Appropriate antibiotic use prevented death at a RR 0.33 (95% CI, 0.21-0.52). Most patients who recovered and survived were treated with aminoglycosides, fluoroquinolones and carbapenems. This review shows the malignant nature of C. violaceum infection and the need for clinicians to be aware and provide prompt source management for patients. Appropriate empiric and targeted antibiotic regiment guided by susceptibility test results is of vital importance.

Geographic Variability and Pathogen-Specific Considerations in the Diagnosis and Management of Chronic Granulomatous Disease

Chronic granulomatous disease (CGD) is a rare but serious primary immunodeficiency with varying prevalence and rates of X-linked and autosomal recessive disease worldwide. Functional defects in the phagocyte nicotinamide adenine dinucleotide phosphate oxidase complex predispose patients to a relatively narrow spectrum of bacterial and fungal infections that are sometimes fastidious and often difficult to identify. When evaluating and treating patients with CGD, it is important to consider their native country of birth, climate, and living situation, which may predispose them to types of infections that are atypical to your routine practice. In addition to recurrent and often severe infections, patients with CGD and X-linked female carriers are also susceptible to developing many non-infectious complications including tissue granuloma formation and autoimmunity. The DHR-123 oxidation assay is the gold standard for making the diagnosis and it along with genetic testing can help predict the severity and prognosis in patients with CGD. Disease management focuses on prophylaxis with antibacterial, antifungal, and immunomodulatory medications, prompt identification and treatment of acute infections, and prevention of secondary granulomatous complications. While hematopoietic stem-cell transplantation is the only widely available curative treatment for patients with CGD, recent advances in gene therapy may provide a safer, more direct alternative.

Chromobacterium violaceum- induced sepsis and multiorgan dysfunction, resembling melioidosis in an elderly diabetic patient: A case report with review of literature

An elderly diabetic farmer presented with chronic nonhealing ulcer over the left foot, multiple liver abscesses, and right-sided pleural effusion. The patient developed septicemia and multiorgan failure. The pus grew pigment producing Chromobacterium violaceum. He was treated successfully with ciprofloxacin for a total duration of 15 days. This case is reported for its rare clinical presentation and resemblance with melioidosis. Of the 200 C. violaceum cases reported across the globe, this is the 14^th case from India and the oldest in the literature.

Programmed Cell Death in the Evolutionary Race against Bacterial Virulence Factors

Innate immune sensors can recognize when host cells are irrevocably compromised by pathogens, and in response can trigger programmed cell death (pyroptosis, apoptosis, and necroptosis). Innate sensors can directly bind microbial ligands; for example, NAIP/NLRC4 detects flagellin/rod/needle, whereas caspase-11 detects lipopolysaccharide. Other sensors are guards that monitor normal function of cellular proteins; for instance, pyrin monitors Rho GTPases, whereas caspase-8 and receptor-interacting protein kinase (RIPK)3 guards RIPK1 transcriptional signaling. Some proteins that need to be guarded can be duplicated as decoy domains, as seen in the integrated decoy domains within NLRP1 that watch for microbial attack. Here, we discuss the evolutionary battle between pathogens and host innate immune sensors/guards, illustrated by the Red Queen hypothesis. We discuss in depth four pathogens, and how they either fail in this evolutionary race (Chromobacterium violaceum, Burkholderia thailandensis), or how the evolutionary race generates increasingly complex virulence factors and host innate immune signaling pathways (Yersinia species, and enteropathogenic Escherichia coli [EPEC]).

Chromobacterium violaceum in Northern Australia: A Sheep in Wolf's Clothing?

In many parts of the world, the case-fatality rate of Chromobacterium violaceum infection approaches 60%. To evaluate the spectrum of disease associated with C. violaceum in Far North Queensland (FNQ), Australia, we reviewed all culture-confirmed isolates from 1997 to 2017. There were 28 isolates, 15 represented infection, 11 were contaminants, and two charts were destroyed preventing detailed evaluation of these cases. The most common sites of infection were the skin and soft tissue and the urinary tract; there were two cases of bacteremia without focus. There were no deaths attributable to C. violaceum during the study period and only two cases required intensive care unit support, although in both patients this was not for the C. violaceum infection, but for the management of other health issues. Globally, C. violaceum has a reputation as a deadly pathogen, but in FNQ, Australia, infections usually follow a relatively benign course.

Necrotizing Pneumonia Caused by Chromobacterium violaceum: Report of a Rare Human Pathogen Causing Disease in an Immunodeficient Child

Chromobacterium violaceum is a rare, potentially serious pathogen. Most clinicians have no experience with its clinical appearance or treatment. We describe a case of a child presenting with necrotizing pneumonia caused by C. violaceum. We describe case complexities, including the need for a multidisciplinary approach to diagnosis and treatment.

Chromobacterium violaceum infection in chronic granulomatous disease: a case report and review of the literature

Introduction.Chromobacterium violaceum is an opportunistic human pathogen, associated with significant mortality, and has been reported in patients with chronic granulomatous disease (CGD), a genetic condition causing impaired phagocytosis.

Case presentation. A 28-year-old man with a history of CGD presented with fever, pharyngitis, cervical lymphadenopathy and internal jugular vein thrombosis, following travel to the rural Solomon Islands. C. violaceum was recovered from his blood. The patient recovered after treatment with meropenem and trimethoprim/sulfamethoxazole.

Conclusion. To the best of our knowledge, this is the first case report of internal jugular vein thrombophlebitis (Lemierre’s syndrome) caused by C. violaceum in a patient with CGD. A review of the literature demonstrated that the diagnosis of C. violaceum preceded the diagnosis of CGD in the majority of cases. This case emphasizes the importance of this organism in patients with CGD who live in or visit tropical areas.

Chromobacterium Violaceum Sepsis: Rethinking Conventional Therapy to Improve Outcome

Patient: Male, 11

Final Diagnosis: Chromobacterium violaceum infection

Symptoms: Abscess • fever • rash

Medication: —

Clinical Procedure: ECMO

Specialty: Critical Care Medicine

Two siblings with fatal Chromobacterium violaceum sepsis linked to drinking water

Chromobacterium violaceum is a Gram-negative organism found in water and soil. C. violaceum is not usually pathogenic in humans; only approximately 150 human cases have been reported worldwide. C. violaceum bacteraemia progresses rapidly, leading to fatal sepsis on dissemination to multiple organs within a short time. We describe two cases of fatal septicaemia caused by C. violaceum in siblings. Our initial impression was that these cases were associated with an undiagnosed immunodeficiency in the siblings. However, detailed patient histories revealed a potential underlying immunodeficiency in only one patient. These findings prompted us to investigate possible environmental exposure. We identified C. violaceum in filtered water that was sold to the family at a nearby store. This discovery led to a public health alert and closer scrutiny of similar stores by the Ministry of Health.

Skin, soft tissue and systemic bacterial infections following aquatic injuries and exposures

: Bacterial infections following aquatic injuries occur commonly in fishermen and vacationers after freshwater and saltwater exposures. Internet search engines were queried with the key words to describe the epidemiology, clinical manifestations, diagnostic and treatment strategies and outcomes of both the superficial and the deeper invasive infections caused by more common, newly emerging and unusual aquatic bacterial pathogens. Main findings included the following: (1) aquatic injuries often result in gram-negative polymicrobial infections with marine bacteria; (2) most marine bacteria are resistant to 1st- and 2nd-generation penicillins and cephalosporins; (3) nontuberculous, mycobacterial infections should be considered in late-onset, culture-negative and antibiotic-resistant marine infections; (4) superficial marine infections and pre-existing wounds exposed to seawater may result in deeply invasive infections and sepsis in immunocompromised patients. With the exception of minor marine wounds demonstrating localized cellulitis, most other marine infections and all gram-negative and mycobacterial marine infections will require therapy with antibiotic combinations.

Skin and soft tissue infections following marine injuries and exposures in travelers

BACKGROUND

Bacterial skin and soft tissue infections (SSTIs) in travelers often follow insect bites and can present a broad spectrum of clinical manifestations ranging from impetigo to necrotizing cellulitis. Significant SSTIs can also follow marine injuries and exposures in travelers, and the etiologies are often marine bacteria.

METHODS

To meet the objectives of describing the pathogen-specific presenting clinical manifestations, diagnostic and treatment strategies, and outcomes of superficial and deep invasive infections in travelers caused by commonly encountered and newly emerging marine bacterial pathogens, Internet search engines were queried with the key words as MESH terms.

RESULTS

Travel medicine practitioners should maintain a high index of suspicion regarding potentially catastrophic, invasive bacterial infections, especially Aeromonas hydrophila, Vibrio vulnificus, Chromobacterium violaceum, and Shewanella infections, following marine injuries and exposures.

CONCLUSIONS

Travelers with well-known risk factors for the increasing severity of marine infections, including those with open wounds, suppressed immune systems, liver disease, alcoholism, hemochromatosis, hematological disease, diabetes, chronic renal disease, acquired immunodeficiency syndrome, and cancer, should be cautioned about the risks of marine infections through exposures to marine animals, seawater, the preparation of live or freshly killed seafood, and the accidental ingestion of seawater or consumption of raw or undercooked seafood, especially shellfish. With the exception of minor marine wounds demonstrating localized cellulitis or spreading erysipeloid-type reactions, most other marine infections and all Gram-negative and mycobacterial marine infections will require therapy with antibiotic combinations.

Chromobacterium violaceum necrotizing fasciitis: a case report and review of the literature

Necrotizing fasciitis is a severe, rapidly progressive infection of the subcutaneous tissue that causes significant destruction. It is rarely encountered in the pediatric population. We describe the case of a 14-year-old boy who was diagnosed with Chromobacterium violaceum necrotizing fasciitis and subsequently found to have autosomal recessive chronic granulomatous disease.

A rare nonfatal presentation of disseminated Chromobacterium violaceum sepsis

We present a case of disseminated Chromobacterium violaceum sepsis with multiple liver and splenic abscesses presenting with skin lesions and cardiogenic shock, and later diagnosed to have chronic granulomatous disease. The patient was treated with prolonged antimicrobial therapy, after which she recovered and remained asymptomatic on follow-up.

Improving care, education, and research: the Asian primary immunodeficiency network

The field of primary immunodeficiencies (PIDs) is marked by continuous discoveries in the mechanisms of disease, genetic etiologies, and treatments. A widening gap between cutting-edge scientific research and its translation to clinical practice is noticeable. To narrow this gap, collaborative networks must be made that bring together a critical mass of specialists to share the knowledge required for the next innovations. In this paper, we describe the current status of the Asian primary immunodeficiency network, which links 40 hospitals in China and Southeast Asia. Over the past 10 years, genetic studies performed on more than 500 patients have led to genetic confirmation of primary immunodeficiency in 272 patients, as well as generating cohort studies that have provided unique phenotypic observations. The network has a dynamic capacity to accommodate priorities and interests of collaborating units, from consultations and genetic testing to scientific research involving next-generation sequencing technologies.

Chromobacterium violaceum infections in 13 non-human primates

BACKGROUND

Recently, an Indian-origin macaque was found dead and Chromobacterium violaceum was isolated from the skin wound, and hepatic and pulmonary abscesses.

METHODS

By searching the database, a total of thirteen cases of C. violaceum infection in pigtail macaques (n = 8), rhesus macaques (n = 4), and one baboon were identified from 2001 to 2010 at Tulane National Primate Research Center. Medical records were reviewed for breed, sex, age, clinical findings, treatment, outcome, bacteriology, and gross and histological findings.

RESULTS

Seven pigtail macaques and one Indian-origin rhesus macaque died of chromobacterial septicemia. All chromobacterial septicemic pigtail macaques were adult with higher incidence in female. Hepatic abscess and thrombosis were typical findings along with pulmonary abscess and thrombosis, renal venous thromboembolism, and necrosuppurative pleuritis, peritonitis, splenitis, myocarditis, pericarditis, and meningoencephalitis. Skin wound, uterine infection, and oral and respiratory exposure were considered the points of entry for these animals.

CONCLUSIONS

This represents the first report of chromobacteriosis in pigtail, rhesus macaque, and baboon. Our experience suggests that chromobacterial infections may be more common in non-human primates than previously recognized.

Nonpigmented Chromobacterium violaceum bacteremic cellulitis after fish bite

A case of nonpigmented Chromobacterium violaceum bacteremic cellulitis after fish bite in Taiwan is reported. The patient was successfully treated with ciprofloxacin and doxycycline for an extended period. Chromobacterium violaceum should be listed in the differential diagnosis of patients with nonspecific cellulitis associated with marked leukocytosis and rapid progression to septicemia either with or without a distinct history of exposure to water or soil. A combination of prompt diagnosis, optimal antimicrobial therapy, and adequate therapeutic duration for C violaceum infection is the key for successful therapy.

Chromobacterium pathogenicity island 1 type III secretion system is a major virulence determinant for Chromobacterium violaceum-induced cell death in hepatocytes

Chromobacterium violaceum is a Gram-negative bacterium that causes fatal septicaemia in humans and animals. C. violaceum ATCC 12472 possesses genes associated with two distinct type III secretion systems (T3SSs). One of these systems is encoded by Chromobacterium pathogenicity islands 1 and 1a (Cpi-1/-1a), another is encoded by Chromobacterium pathogenicity island 2 (Cpi-2). Here we show that C. violaceum causes fulminant hepatitis in a mouse infection model, and Cpi-1/-1a-encoded T3SS is required for its virulence. In addition, using C. violaceum strains with defined mutations in the genes that encode the Cpi-1/-1a or Cpi-2 locus in combination with cultured mammalian cell lines, we found that C. violaceum is able to induce cytotoxicity in a Cpi-1/-1a-dependent manner. Characterization of Chromobacterium-induced cytotoxicity revealed that cell lysis by C. violaceum infection involves the formation of pore structures on the host cell membrane, as demonstrated by protection by cytotoxicity in the presence of osmoprotectants. Finally, we demonstrated that CipB, a Cpi-1/-1a effector, is implicated in translocator-mediated pore formation and the ability of CipB to form a pore is essential for Chromobacterium-induced cytotoxicity. These results strongly suggest that Cpi-1/-1a-encoded T3SS is a virulence determinant that causes fatal infection by the induction of cell death in hepatocytes.

Computational analysis suggests that virulence of Chromobacterium violaceum might be linked to biofilm formation and poly-NAG biosynthesis

Groups of genes that produce exopolysaccharide with a N-acetyl-D-glucosamine monomer are in the genome of several pathogenic bacteria. Chromobacterium violaceum, an opportunistic pathogen, has the operon hmsHFR-CV2940, whose proteins can synthesize such polysaccharide. In this work, multiple alignments among proteins from bacteria that synthesize such polysaccharide were used to verify the existence of amino acids that might be critical for pathogen activity. Three-dimensional models were generated for spatial visualization of these amino acid residues. The analysis carried out showed that the protein HmsR preserves the amino acids D135, D228, Q264 and R267, considered critical for the formation of biofilms and, furthermore, that these amino acids are close to each other. The protein HmsF of C. violaceum preserves the residues D86, D87, H156 and W115. It was also shown that these residues are also close to each other in their spatial arrangement. For the proteins HmsH and CV2940 there is evidence of conservation of the residues R104 and W94, respectively. Conservation and favorable spatial location of those critical amino acids that constitute the proteins of the operon indicates that they preserve the same enzymatic function in biofilm synthesis. This is an indicator that the operon hmsHFR-CV2940 is a possible target in C. violaceum pathogenicity.

Septicemia in a neonatal calf associated with Chromobacterium violaceum

Chromobacterium violaceum infections are highly fatal and rarely reported in domestic animals. This report describes a fatal case of C. violaceum septicemia in a 7-day-old female beef calf. The calf had necrosuppurative omphalophlebitis, necrotizing interstitial pneumonia, necrosuppurative hepatitis and splenitis, anterior uveitis with hypopyon, suppurative polyarthritis, and disseminated hemorrhagic meningitis with multifocal necrotizing encephalitis. Histologically, clusters of gram-negative bacilli were found in many of the lesions. C. violaceum was isolated in high numbers from the lungs, liver, spleen, carpus, and in pure culture from the cerebrospinal fluid. To our knowledge, this is the first case report of chromobacteriosis in a calf.

Fatal septicemia caused by Chromobacterium violaceum in a child from Colombia

A 4-year old child living in Colombia presented with a history of fever and severe abdominal pain for four days. The patient developed pneumonia, septic shock, multiple organ failure and died on the fifth day of hospitalization. Chromobacterium violaceum was isolated from admission blood cultures and was resistant to ampicillin, cephalosporins, carbapenems and aminoglycosides.

Susceptibility to mycobacterial infections in children with X-linked chronic granulomatous disease: a review of 17 patients living in a region endemic for tuberculosis

BACKGROUND

Chronic granulomatous disease (CGD) is a rare disorder of phagocytic oxidative bursts leading to recurrent pyogenic infections. Affected individuals are most prone to infections caused by staphylococci, Salmonella, Candida, and Aspergillus, but previously we observed a high incidence of Mycobacterium tuberculosis infection in Chinese children with CGD.

OBJECTIVE

To determine the spectrum of infections in patients with X-linked CGD, with an emphasis on mycobacterial infections, and to review all CYBB gene mutations identified in our center.

RESULTS

From 1988 to 2005, 17 Chinese male children were diagnosed to have X-linked CGD. Fifteen mutations were identified, including 3 splice site defects (IVS1-1G>C, 266G>A, IVS3-1G>A), 5 missense mutations (591T>C, 627T>A, 949T>A, 1039T>A, 1512G>C), 3 nonsense mutations (882C>T, 1451C>A, 1569G>T), 1 insertion (756_757insA), and 3 deletions (660_662delTTC, 727delT, 1341delT). Eight of these were novel mutations. Recurrent pneumonia, lymphadenitis, and bacterial skin abscess were the commonest types of infection. Seven patients had tuberculosis (TB). Seven patients had prolonged scarring or abscess formation at the Calmette-Guérin bacillus (BCG) injection site, and 1 had disseminated BCG infection. Three patients had pulmonary aspergillosis. Four patients underwent hemopoietic stem cell transplantation, but 2 died of complications.

CONCLUSIONS

Patients with CGD are susceptible to TB and BCG complications. Our observation suggests that oxidative burst is probably important in host defense against mycobacterial infections. Because interferon-gamma is the key cytokine involved in mycobacterial immunity, there may be a stronger indication for its use in CGD patients living in areas endemic for TB.

Chromobacterium violaceum infection in two dogs

Chromobacterium violaceum is a saprophyte of soil and water in tropical and subtropical environments that is associated with rare but highly fatal infections in animals and humans. Systemic infection was diagnosed in two critically ill dogs from Florida. Fever was absent in both dogs. Both dogs were treated surgically and provided with intensive care, but only one survived. The identification of characteristic, violet-pigmented bacterial colonies on routine microbial cultures should alert microbiologists and clinicians to the likelihood of this dangerous pathogen. Because of the rapidly progressive nature of this infection, empirical antibiotic administration with fluoroquinolones should be employed pending susceptibility testing.

Ecthyma gangrenosum and septic shock syndrome secondary to Chromobacterium violaceum

Chromobacterium violaceum is a gram-negative bacterium of soil and water in tropical and subtropical environments. Typically, it is considered a bacterium of low virulence although, uncommonly, it causes human infection, particularly in persons with defects in host defenses. Infection generally follows exposure of broken skin to contaminated water and soil, and is often characterized by pustules, lymphadenitis, fever, and vomiting, as well as rapid dissemination and a high mortality rate. Unfortunately, because C violaceum is ubiquitous, it is often dismissed as a contaminant when cultured. Because rapid diagnosis (by taking appropriate specimens) and treatment are vital to a good prognosis, it is imperative that physicians be aware of this organism. In addition, patients with chromobacterial infections should have an immunologic workup because infections in immunocompetent individuals are rare. Here we report an aggressive yet nonfatal case of C violaceum septicemia in an adolescent male, diagnosed through a punch biopsy of a skin lesion, and resulting in a new diagnosis of chronic granulomatous disease.

Chromobacterium violaceum in siblings, Brazil

Chromobacterium violaceum, a saprophyte bacterium found commonly in soil and water in tropical and subtropical climates, is a rare cause of severe, often fatal, human disease. We report 1 confirmed and 2 suspected cases of C. violaceum septicemia, with 2 fatalities, in siblings after recreational exposure in northeastern Brazil.

A case of Chromobacterium infection after car accident in Korea

Chromobacterium violaceum is a gram negative straight rod, 0.8-1.2 by 2.5 to 6.0 m, which is motile by one polar flagella and one to four lateral flagella. The organism inhabits soil and water and is often found in semitropical and tropical climates. Infections in humans are rare. We report a case of infection caused by strains of C. violaceum. A 38-year-old male patient was admitted to KyungHee University Hospital, Seoul, Korea on July 28th, 2003, after a car accident. The patient had multiple trauma and lacerations. He had an open wound in the left tibial area from which C. violaceum was isolated. The strain was resistant to ampicillin, tobramycin, ampicillin/sulbactam, ceftriaxone and cefepime, but was susceptible to amikacin, gentamicin, ciprofloxacin, levofloxacin, trimethoprim/sulfamethoxazole and piperacillin/tazobactam. The patient was treated successfully by debridement, cephapirin sodium and astromicine sulfate.

Detection of Chromobacterium violaceum by multiplex PCR targeting the prgI, spaO, invG, and sipB genes

Based on the recently completed genomic sequence of Chromobacterium violaceum American Type Culture Collection (ATCC) 12472 a multiplex PCR assay targeting the prgI, spaO, invG, and sipB genes of the Salmonella SPI-1 homologue type-III secretion system was developed. PCR products of 255bp (prgI), 749bp (spaO), 1685bp (invG), and 1752bp (sipB) were successfully amplified simultaneously in a single reaction with all Chr. violaceum strains investigated whereas other bacteria tested negative. The detection limit for pure cultures in multiplex PCR analysis was 100CFU. The developed assay significantly improves rapid identification of Chr. violaceum and allows its differentiation from closely related organisms.

Invasive Chromobacterium violaceum infection in children: case report and review

A 3.3-year-old boy developed Chromobacterium violaceum abscesses of lungs, liver and spleen and was successfully treated. He had chronic granulomatous disease (CGD). Twenty-five episodes of invasive C. violaceum infection in 24 children were reviewed. All 9 CGD and 10 nonbacteremic cases survived, but 12 of 16 (75%) non-CGD and 12 of 15 (80%) bacteremic patients died.

Infections in patients with inherited defects in phagocytic function

Patients with defects in phagocytic function are predisposed to intracellular microorganisms and typically have early dissemination of the infection. Recognition of the underlying disorder and aggressive antimicrobial therapy has been beneficial for the patients. Improved understanding of the pathophysiology has also affected patient management by allowing specific, targeted immunomodulatory intervention. The disorders described in this review are not common but have had a significant impact on our understanding of the role of phagocytic cells in host defense. Conversely, understanding the role of the neutrophil and macrophage in infection has benefited not just the patients described in this review but also other patients with similar disease processes.

Chromobacterium violaceum infection in children: a case of fatal septicemia with nasopharyngeal abscess and literature review

This previously healthy 5-year-old boy initially presented with fever and purulent conjunctivitis. The course evolved rapidly into preseptal and facial cellulitis, nasopharyngeal abscess and sepsis. Chromobacterium violaceum was isolated from conjunctival exudate and blood cultures. He received intravenous cefazolin therapy for 2 days, followed by penicillin, oxacillin and netilmicin. However, no improvement was noted, and he died on the fifth days of illness.

Chromobacterium violaceum: a case of diarrhea in Senegal

A 5-year-old infant with diarrhea had heavy growth of Chromobacterium violaceum cultured from stool. This organism is restricted geographically between latitudes 35 degrees N and 35 degrees S. It can cause sepsis and various focal infections but is not a well-known cause of diarrhea.

Chromobacterium violaceum septicemia

Chromobacterium violaceum is an extremely rare human pathogen. We report a rare case of septicemia with multiple abscesses and otitis media in a newborn caused by chromobacterium violaceum.

Chromobacterium violaceum infection: A rare but frequently fatal disease

The authors report a rare case of Chromobacterium violaceum infection in a 2-month-old child. She presented with an apparently localized abscess, which appeared to respond well to therapy. However, the infection recurred later with a fulminant course. The organism frequently is dismissed as a contaminant or not identified properly, and the fatality rates are high. A high degree of awareness about this infection needs to be created, especially among pediatricians and pediatric surgeons, because children appear to be infected more commonly than adults, and aggressive therapy is needed to save these patients.

Expression and partial characterization of an elastase from Chromobacterium violaceum

Chromobacterium violaceum was recovered at necropsy from the lungs, liver, spleen, and an interscapular abscess of a Chinese red panda (strain 98-9187) [J. Vet. Diagn. Invest. 12 (2000) 177]. As the lungs exhibited extensive, necrotizing lesions harboring bacterial aggregates, we sought to determine whether C. violaceum produced an elastase that might in part account for these lesions. The C. violaceum type strain (ATCC 12472(T)) and strain 98-9187 were shown to exhibit elastolytic activity by elastin Congo red and elastin nutrient agar assays. The activity was isolated from the periplasmic fraction and was present throughout the growth cycle. Activity increased markedly in late logarithmic phase growth. In elastin-limiting medium, activity rapidly decreased in early stationary phase indicating a tight regulation of yield. The activity was optimal at neutral pH and was sensitive to the metalloproteinase inhibitors EDTA and 1,10-phenanthroline. Activity was restored upon addition of zinc indicating the enzyme is a zinc metalloproteinase. A band corresponding to purified elastase activity was present at approximately 30kDa in a denaturing polyacrylamide gel.

Successful treatment of an infant with Chromobacterium violaceum sepsis

Chromobacterium violaceum sepsis, a rarely reported phenomenon, has a high mortality rate. We report a unique case of C. violaceum sepsis in an infant. A 4-month-old girl presented to our institution with fever, pustular skin lesions, and distended abdomen, as well as diminished activity and mental status. Radiological investigation revealed brain, lung, and hepatic abscesses. The infant was successfully treated with trimethoprim-sulfamethoxazole and ciprofloxacin.

Genetic, biochemical, and clinical features of chronic granulomatous disease

The reduced nicotinamide dinucleotide phosphate (NADPH) oxidase complex allows phagocytes to rapidly convert O2 to superoxide anion which then generates other antimicrobial reactive oxygen intermediates, such as H2O2, hydroxyl anion, and peroxynitrite anion. Chronic granulomatous disease (CGD) results from a defect in any of the 4 subunits of the NADPH oxidase and is characterized by recurrent life-threatening bacterial and fungal infections and abnormal tissue granuloma formation. Activation of the NADPH oxidase requires translocation of the cytosolic subunits p47phox (phagocyte oxidase), p67phox, and the low molecular weight GT-Pase Rac, to the membrane-bound flavocytochrome, a heterodimer composed of the heavy chain gp91phox and the light chain p22phox. This complex transfers electrons from NADPH on the cytoplasmic side to O2 on the vacuolar or extracellular side, thereby generating superoxide anion. Activation of the NADPH oxidase requires complex rearrangements between the protein subunits, which are in part mediated by noncovalent binding between src-homology 3 domains (SH3 domains) and proline-rich motifs. Outpatient management of CGD patients relies on the use of prophylactic antibiotics and interferon-gamma. When infection is suspected, aggressive effort to obtain culture material is required. Treatment of infections involves prolonged use of systemic antibiotics, surgical debridement when feasible, and, in severe infections, use of granulocyte transfusions. Mouse knockout models of CGD have been created in which to examine aspects of pathophysiology and therapy. Gene therapy and bone marrow transplantation trials in CGD patients are ongoing and show great promise.

Chromobacterium violaceum diarrhea

This is the first case of Chromobacterium violaceum diarrhoea from coastal Karnataka reported in a 2 year 10 months old girl. Stool culture yielded Chromobacterium violaceum and was sensitive to ampicillin, gentamicin, chloramphenicol, erythromycin and septran. Patient completely recovered with ampicillin and gentamicin.

Chromobacteriosis in a Chinese red panda (Ailurus fulgens styani)

An adult Chinese red panda (Ailurus fulgens styani) transported by airplane from Florida to a North Dakota zoo died 1 week after arrival. Grossly, an interscapular abscess, subcutaneous inflammation, lymphadenitis, and pulmonary abscesses were observed. Microscopic findings included necrotizing inflammation in liver, lung, lymph node, and spleen. Chromobacterium violaceum was cultured from the interscapular abscess, liver, lung, and spleen and was injected into Swiss Webster mice. These mice died 18 hours postinoculation, and C. violaceum was cultured from liver, lung, and spleen. Chromobacterium violaceum is a sporadically reported but highly virulent pathogenic bacterium of both animals and humans typically found as a soil and water inhabitant of tropical and subtropical regions.

Two cases of Chromobacterium violaceum infection after injury in a subtropical region

Chromobacterium violaceum is a gram-negative rod and is isolated from soil and water in tropical and subtropical regions. The species have pigmented and nonpigmented colony types. Infections caused by nonpigmented strains are rare. We report on two cases of infection caused by both pigmented and nonpigmented strains of C. violaceum. Two 24-year-old Korea Airline stewardesses were admitted to Inha University Hospital, Inchon, South Korea, on 9 August 1997, 3 days after an airplane accident in Guam. Both had multiple lacerations on exposed parts of their bodies. There was swelling, tenderness, and pus discharge. The wounds contained many small fragments of stones and weeds. A pigmented strain was isolated from the left hand and a nonpigmented strain was isolated from the left knee of one patient. For the other patient only a nonpigmented strain was isolated from a foot wound. The nonpigmented colonies from the left-knee and the left-foot wounds did not produce any pigment even after an extended period of incubation. The biochemical characteristics were the same for each strain except for oxidase and indole reactions. The pigmented strain was oxidase negative and indole positive, whereas the nonpigmented strains were oxidase positive and indole negative. The patients were successfully treated by debridement and with appropriate antibiotics.

Chromobacterium violaceum in tropical northern Australia

Chromobacterium violaceum is an unusual cause of infection which may have fatality rates of over 60% when systemic illness occurs. We describe four patients infected with this organism who were successfully treated at Royal Darwin Hospital between 1991 and 1996. In tropical Australia, C. violaceum infection should be considered along with melioidosis in patients who present with a septic illness with skin lesions and/or organ abscesses after exposure to soil in the wet season.

Chromobacterium violaceum septicaemia: the intensive care management of two cases

The first human infection with Chromobacterium violaceum was recorded in 1927, but since then there have been about 33 cases reported worldwide, including two from Australia. Chr. violaceum occurs in the tropics and subtropics and is generally considered to be nonpathogenic, but infection can occur in patients who are immunosuppressed and it has a high mortality rate. This paper presents the intensive care management of two cases of Chr. violaceum infection occurring in Far North Queensland. The patients' predisposition appears to have been malnourishment and alcohol abuse. The increased use of immunosuppressive drugs and the appearance of diseases such as acquired immune deficiency syndrome (AIDS) make it possible that we will see more of this condition in Australian intensive care units.