Chromobacterium violaceum infection on lower limb skin: A case report

RATIONAL

Chromobacterium violaceum is a motile gram-negative bacterium. This bacterium commonly grows in tropical or subtropical areas in sewage and can cause opportunistic infections.

PATIENT CONCERNS

A 50-year-old Chinese man had a skin ulcer in the middle of his left leg in front of the tibia. The diameter of the wound was 3.0 cm, the exudation was obvious, and necrotic tissue was attached to the wound. One week previously, he was working in a field where he accidentally punctured his left leg.

DIAGNOSIS

C violaceum infection was diagnosed as per the results of pathogen culture from the infection site.

INTERVENTIONS

He was treated with piperacillin/tazobactam (3.375 g/12 h iv) and levofloxacin (0.5 g/24 h iv) for 5 days.

OUTCOMES

The patient showed good response to therapy and was discharged on day 18 after wound healing.

LESSONS

C violaceum rarely infects humans. When an infection is suspected, samples should be immediately sent for microbial culture. Timely treatment on the basis of drug sensitivity test results can prevent further complications.

Sepsis caused by Chromobacterium violaceum - probably the first case in Europe, or Macbeth read anew

Rare diseases, almost by definition, present us with diagnostic as well as therapeutic difficulties as. They also include infectious diseases outside endemic areas. Without expecting them, we are not preparing to fight them. Like Macbeth, we feel safe, convinced that tropical diseases do not reach us, like Birnam forest towards his castle. Nevertheless, the forest moved according to the prophecy of the three witches, and in a similar way tropical flora is moving towards us according to the predictions of environmentalists. This is illustrated by the history of the presented patient, who was admitted to hospital because of sepsis caused by Chromobacterium violaceum (CV), a Gram-negative facultatively anaerobic, oxidase-positive bacterium producing a dark violet antioxidant pigment called violacein. This is probably the first documented case report of sepsis in this part of the world. To the best of the authors' knowledge, the patient is the first to require dialysis after Chromobacterium violaceum infection.

Chromobacterium violaceum: The Deadly Sepsis

Chromobacterium violaceum is a Gram-negative facultatively anaerobic, oxidase-positive bacterium producing a dark violet antioxidant pigment called violacein. It is an opportunistic pathogen and has an ubiquitous distribution, mainly resides in water and soil of tropical and subtropical regions.An-18-year-old man referred to the emergency room with a 5-day history of progressively worsening swelling of the right cheek. He sought consult and hospitalized at another institution for three days prior this admission; however, his condition deteriorated. He had a history of having abscesses several time. Four month before this visit, he was also admitted in our hospital due to an abscess in the right thigh. Pus and blood culture were positive for Staphylococcus haemolyticus, with a total serum IgE of 2493.0 IU/ml. He recovered completely after being treated with vancomycin in this event. He had neither diabetes mellitus nor human immunodeficiency virus infection history. In this presentation, he was in a critically ill state with septic shock. Physical examination revealed diffuse, indurated, partly fluctuant, and some deep purple area of right hemifacial swelling. It was extended anteriorly from angle of mouth to retroauricular, superiorly from superior palpebra to lower border of mandible. Laboratory studies were notable for a white-cell count of 12,970/mm3 (total lymphocyte count 778.2), platelet count 96,000/mm3. The patient got norepinephrine drip and broad-spectrum antibiotic intravenously. He also underwent superficial drainage of the abscess. Unfortunately, the patient eventually succumbed. Sample from right submandibular abscess showed no growth, but blood sample was confirmed to grow C. violaceum. It showed sensitivity to ciprofloxacin, amikacin, cotrimoxazole, chloramphenicol, tetracycline.Since it was firstly described in 1927, only a few cases of human infection with C. violaceum have been reported. As shown in our case, the classical clinical manifestation was localized soft tissue infection which rapidly progressed to fulminant sepsis with a high mortality rate. A defect in host defense system might be the predisposing factor for this kind of infection in our case. As this is such a rare infection, there is no guideline on the choice of antibiotics or duration of treatment at present. Successful treatment is most likely due to early recognition, prompt surgical drainage and appropriate antibiotic. To the best of our knowledge, this is the first reported case from Indonesia that could be identified in the literature.

Multiple Liver Abscesses with a Skin Pustule due to Chromobacterium violaceum

A 69-year-old woman was admitted to our hospital with the chief complaints of fever and fatigue. We initially treated the patient for a tick-borne disease after noticing a pustule on her leg; however, abdominal computed tomography (CT) showed multiple low-density areas in the liver and Chromobacterium violaceum was isolated from a blood culture. We diagnosed her with multiple liver abscesses secondary to Chromobacterium violaceum bacteremia. The patient was successfully treated with ciprofloxacin.

Pediatric bacteremia caused by Chromobacterium haemolyticum/Chromobacterium aquaticum

We present a case of pediatric bacteremia caused by Chromobacterium haemolyticum, a β-hemolytic, non-pigmented, Gram-negative bacilli recovered from a blood culture and initially identified as Chromobacterium violaceum using phenotypic and proteomic methods. 16S rRNA sequencing of the patient isolated demonstrated a high degree of sequence homology with the type strain of C. haemolyticum. The patient recovered following treatment with meropenem, gentamicin, and trimethoprim/sulfamethoxazole. This case highlights the potential misidentification of C. haemolyticum as non-pigmented C. violaceum due to limitations of the currently available identification methodologies.

Chromobacterium amazonense sp. nov. isolated from water samples from the Rio Negro, Amazon, Brazil

The taxonomic position of a bacterium isolated from water samples from the Rio Negro, in Amazon, Brazil, was determined by using a polyphasic approach. The organism formed a distinct phyletic line in the Chromobacterium 16S rRNA gene tree and had chemotaxonomic and morphological properties consistent with its classification in this genus. It was found to be closely related to Chromobacterium vaccinii DSM 25150(T) (98.6 % 16S rRNA gene similarity) and shared 98.5 % 16S rRNA gene similarity with Chromobacterium piscinae LGM 3947(T). DNA-DNA relatedness studies showed that isolate CBMAI 310(T) belongs to distinct genomic species. The isolate was readily distinguished from the type strain of these species using a combination of phenotypic and chemotaxonomic properties. Thus, based on genotypic and phenotypic data, it is proposed that isolate CBMAI 310(T) (=DSM 26508(T)) be classified in the genus Chromobacterium as the type strain of a novel species, namely, Chromobacterium amazonense sp. nov.

Quorum quenching in culturable phyllosphere bacteria from tobacco

Many Gram-negative plant pathogenic bacteria employ a N-acylhomoserine lactone (AHL)-based quorum sensing (QS) system to regulate their virulence traits. A sustainable biocontrol strategy has been developed using quorum quenching (QQ) bacteria to interfere with QS and protect plants from pathogens. Here, the prevalence and the diversity of QQ strains inhabiting tobacco leaf surfaces were explored. A total of 1177 leaf-associated isolates were screened for their ability to disrupt AHL-mediated QS, using the biosensor Chromobacterium violaceum CV026. One hundred and sixty-eight strains (14%) are capable of interfering with AHL activity. Among these, 106 strains (63%) of the culturable quenchers can enzymatically degrade AHL molecules, while the remaining strains might use other QS inhibitors to interrupt the chemical communication. Moreover, almost 79% of the QQ strains capable of inactivating AHLs enzymatically have lactonase activity. Further phylogenetic analysis based on 16S rDNA revealed that the leaf-associated QQ bacteria can be classified as Bacillus sp., Acinetobacter sp., Lysinibacillus sp., Serratia sp., Pseudomonas sp., and Myroides sp. The naturally occurring diversity of bacterial quenchers might provide opportunities to use them as effective biocontrol reagents for suppressing plant pathogen in situ.

A successful antimicrobial regime for Chromobacterium violaceum induced bacteremia

BACKGROUND

Chromobacterium violaceum is a proteobacterium found in soil and water in tropical regions. The organism rarely causes infection in humans, yet can cause a severe systemic infection by entering the bloodstream via an open wound.

CASE PRESENTATION

We recently identified a case of severe bacteremia caused by Chromobacterium violaceum at the Hospital for Tropical Diseases (HTD) in Ho Chi Minh City, Vietnam. Here, we describe how rapid microbiological identification and a combination of antimicrobials was used to successfully treat this life threatening infection in a four-year-old child.

CONCLUSIONS

This case shows the need for rapid diagnosis when there is the suspicion of a puncture wound contaminated with water and soil in tropical regions. We suggest that the aggressive antimicrobial combination used here is considered when this infection is suspected.

Detection, characterization, and biological effect of quorum-sensing signaling molecules in peanut-nodulating bradyrhizobia

Bacteria of the genus Bradyrhizobium are able to establish a symbiotic relationship with peanut (Arachis hypogaea) root cells and to fix atmospheric nitrogen by converting it to nitrogenous compounds. Quorum sensing (QS) is a cell-cell communication mechanism employed by a variety of bacterial species to coordinate behavior at a community level through regulation of gene expression. The QS process depends on bacterial production of various signaling molecules, among which the N-acylhomoserine lactones (AHLs) are most commonly used by Gram-negative bacteria. Some previous reports have shown the production of QS signaling molecules by various rhizobia, but little is known regarding mechanisms of communication among peanut-nodulating strains. The aims of this study were to identify and characterize QS signals produced by peanut-nodulating bradyrhizobial strains and to evaluate their effects on processes related to cell interaction. Detection of AHLs in 53 rhizobial strains was performed using the biosensor strains Agrobacterium tumefaciens NTL4 (pZLR4) and Chromobacterium violaceum CV026 for AHLs with long and short acyl chains, respectively. None of the strains screened were found to produce AHLs with short acyl chains, but 14 strains produced AHLs with long acyl chains. These 14 AHL-producing strains were further studied by quantification of β-galactosidase activity levels (AHL-like inducer activity) in NTL4 (pZLR4). Strains displaying moderate to high levels of AHL-like inducer activity were subjected to chemical identification of signaling molecules by high-performance liquid chromatography coupled to mass spectrometry (LC-MS/MS). For each AHL-producing strain, we found at least four different AHLs, corresponding to N-hexanoyl-dl-homoserine lactone (C₆), N-(3-oxodecanoyl)-l-homoserine lactone (3OC₁₀), N-(3-oxododecanoyl)-l-homoserine lactone (3OC₁₂), and N-(3-oxotetradecanoyl)-l-homoserine lactone (3OC₁₄). Biological roles of 3OC10, 3OC12, and 3OC14 AHLs were evaluated in both AHL-producing and -non-producing peanut-nodulating strains. Bacterial processes related to survival and nodulation, including motility, biofilm formation, and cell aggregation, were affected or modified by the exogenous addition of increasing concentrations of synthetic AHLs. Our results clearly demonstrate the existence of cell communication mechanisms among bradyrhizobial strains symbiotic of peanut. AHLs with long acyl chains appear to be signaling molecules regulating important QS physiological processes in these bacteria.

Production and characterization of violacein by locally isolated Chromobacterium violaceum grown in agricultural wastes

The present work highlighted the production of violacein by the locally isolated Chromobacterium violaceum (GenBank accession no. HM132057) in various agricultural waste materials (sugarcane bagasse, solid pineapple waste, molasses, brown sugar), as an alternative to the conventional rich medium. The highest yield for pigment production (0.82 g L⁻¹) was obtained using free cells when grown in 3 g of sugarcane bagasse supplemented with 10% (v/v) of L-tryptophan. A much lower yield (0.15 g L⁻¹) was obtained when the cells were grown either in rich medium (nutrient broth) or immobilized onto sugarcane bagasse. Violacein showed similar chemical properties as other natural pigments based on the UV-Vis, Fourier transform infrared spectroscopy, thin-layer chromatography, nuclear magnetic resonance, and mass spectrometry analysis. The pigment is highly soluble in acetone and methanol, insoluble in water or non-polar organic solvents, and showed good stability between pH 5-9, 25-100 °C, in the presence of light metal ions and oxidant such as H₂O₂. However, violacein would be slowly degraded upon exposure to light. This is the first report on the use of cheap and easily available agricultural wastes as growth medium for violacein-producing C. violaceum.

Chromobacterium violaceum lymphadenitis successfully treated in a Northern Italian hospital

Lymphadenitis can be caused by different gram positive and gram negative bacteria and non-tuberculous mycobacteria. Cervical lymphadenitis in children is thought to result from ingestion of or contact with environmental microrganisms. Chromobacterium violaceum is a common inhabitant of soil and water in tropical and sub tropical countries. In these parts of the world Chromobacterium violaceum is able to cause skin infection with diffuse pustular lesions and also multiple liver abscess with often fatal evolution in sepsis. We describe a case of cervical lymphadenitis caused by Chromobacterium violaceum in a 14-year-old boy, born in Guinea and resident in Italy for 7 years in a fair condition with general measurable swelling in the right lateral cervical region and with blood tests that showed increased inflammatory indices. The patient was subjected to surgical incision. Antibiotic therapy with ceftriaxone was continued for 10 days, then replaced successfully with oral ciprofloxacin on the basis of purulent material culture positive for Chromobacterium violaceum sensitive to fluoroquinolones.

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 violaceum sepsis in an infant

Chromobacterium violaceum is a rare pathogen that can cause potentially fatal infections in humans. Till date, 150 cases are reported worldwide including 7 from India. We report a 6 month old infant who presented with high grade fever, respiratory distress and multiple vesicular skin lesions. Chromobacterium violaceum was isolated from blood, bone marrow aspirate and from skin lesions. Infant responded to treatment with piperacillin and ciprofloxacin, and is doing well on follow up.

Diversity in antifungal activity of strains of Chromobacterium violaceum from the Brazilian Amazon

Chromobacterium violaceum is a free-living Gram-negative bacterium found in soil and aquatic habitats; abundantly present in the Brazilian Amazon, it is an important example of exploitable microbial diversity of the tropics. In this study, 24 strains from the Brazilian Amazon and ATCC 12472(T) were investigated for biocontrol potential of seven fungi pathogenic to soybean [Glycine max (L.) Merril] seed. Both cells and the supernatants of two Brazilian strains, 07-1 and 27-1, together with ATCC 12472(T) were strongly antagonistic to six out of the seven fungi. The antifungal activity of the Brazilian strains to Fusarium sp., Phomopsis sp. and Cercospora kikuchi was consistently stronger than that of ATCC 12472(T). In addition, the two Brazilian strains, but not ATCC 12472(T), were effective against Corynespora sp., and all three strains and their supernatants were equally effective against Aspergillus sp. and Colletotrichum sp. None of the strains had antifungal activity against Botroyodiplodia sp. Three potential mechanisms related to the antibiosis were investigated: violacein toxicity, cyanide production and chitinolytic activity; however, it was not possible to associate any of them with the antifungal activity. The results highlight the biotechnological potential still to be explored within the poorly characterized microbial biodiversity of the tropics.

Purification and characterization of Chromobacterium sp. DS-1 cholesterol oxidase with thermal, organic solvent, and detergent tolerance

A new screening method for 6beta-hydroperoxycholest-4-en-3-one (HCEO)-forming cholesterol oxidase was devised in this study. As the result of the screening, a novel cholesterol oxidase producer (strain DS-1) was isolated and identified as Chromobacterium sp. Extracellular cholesterol oxidase of strain DS-1 was purified from the culture supernatant. The molecular mass of the purified enzyme was 58 kDa. This enzyme showed a visible adsorption spectrum having peaks at 355 and 450 nm, like a typical flavoprotein. The enzyme oxidized cholesterol to HCEO, with the consumption of 2 mol of O2 and the formation of 1 mol of H2O2 for every 1 mol of cholesterol oxidized. The enzyme oxidized 3beta-hydroxysteroids such as cholesterol, beta-cholestanol, and pregnenolone at high rates. The Km value for cholesterol was 26 microM. The enzyme was stable at pH 3 to 11 and most active at pH 7.0-7.5, showing optimal activity at pH 7.0 and 65 degrees C. The enzyme retained about 80% of its activity after incubation for 30 min at 85 degrees C. The thermal stability of the enzyme was the highest among the cholesterol oxidases tested. Moreover, the enzyme was more stable in the presence of various organic solvents and detergents than commercially available cholesterol oxidases.

Human Chromobacterium violaceum infection in Southeast Asia: case reports and literature review

Chromobacterium violaceum infection in humans is a rare tropical and subtropical disease. The awareness of this organism is limited in spite its ubiquitous distribution. Several cases have been reported from Southeast Asia. A localized infection followed by an overwhelming septicemia and metastatic lesions is the usual pattern of this illness. Optimal antimicrobial treatment and duration are unknown. Consequently, the outcome is usually fatal. The study reported two patients who suffered from fulminant Chromobacterium violaceum sepsis with disseminated infection, and reviews the literature for cases reported from Southeast Asia.

Chromobacterium violaceum cellulitis and sepsis following cutaneous marine trauma

Chromobacterium violaceum is a gram-negative bacillary organism that characteristically produces the purple pigment violacein. Documented as the cause of clinically relevant human infections in only 35 cases in the United States, C violaceum is particularly seen in patients with a history of cutaneous injury or trauma. We report the case of an 18-year-old woman who was struck by a propeller in a boating accident and sustained multiple deep lacerations of her right lower extremity. Shortly after admission to the hospital, the patient became frebrile and developed leukocytosis. Bacterial cultures revealed C violaceum, which demonstrated a characteristic purple pigment production on blood agar. Antimicrobial therapy was initiated, but 2 days after admission, the skin and subcutaneous tissue surrounding the patient's wounds became necrotic, necessitating an above-the-knee amputation of the right lower extremity (transfemoral amputation). The patient's condition improved after continued antimicrobial therapy and she was subsequently discharged in good health. This case represents a successful outcome of a rare but frequently fatal infection due to a morphologically and geographically distinct human pathogen.

Sepsis by Chromobacterium violaceum: first case report from Colombia

Chromobacterium violaceum is found in tropical and subtropical regions; it is the only Chromobacterium species pathogenic for humans. Due to its rare presentation, physicians often ignore the importance of this pathogen. We report a fulminant fatal case of bacteremia in a 38-year-old Colombian man. The clinical manifestations were fever, thoracic pain, respiratory failure and death. His condition, from the beginning of clinical diagnosis, went into continuous deterioration, till his death, within a few days after the symptoms began. Two hemocultures isolated C. violaceum. We conclude that doctors should consider this differential diagnosis in patients with systemic inflammatory response syndrome, with continuous deterioration.

Fatal septicaemia due to Chromobacterium violaceum

Human infection caused by Chromobacterium violaceum is rare but when it occurs, it is associated with a high mortality rate. This is a report of a young adult male who presented as a surgical emergency and succumbed soon after. The most common feature of this infection is sepsis, followed by cutaneous involvement and liver abscesses. Chromobacterium infection as a differential in a case of sepsis is important for clinicians to suspect, especially in tropical countries.

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.

Chromobacterium subtsugae sp. nov., a betaproteobacterium toxic to Colorado potato beetle and other insect pests

Strain PRAA4-1(T), a motile, Gram-negative, violet-pigmented bacterium, was isolated from Maryland forest soil and found to be orally toxic to Colorado potato beetle larvae and other insects. Morphological, biological, biochemical and molecular characterization revealed that this strain was most similar to Chromobacterium violaceum, the type species and only currently recognized member of the genus Chromobacterium. DNA-DNA hybridization with C. violaceum ATCC 12472(T) was 27 %. Phylogenetic analysis of 16S rRNA gene sequences revealed that strain PRAA4-1(T) and Chromobacterium violaceum form a monophyletic clade, with the closest ancestral taxon Vogesella indigofera within the Betaproteobacteria. On the basis of phenotypic, genotypic and phylogenetic analyses, strain PRAA4-1(T) (=NRRL B-30655(T)=DSM 17043(T)) is proposed as the type strain of a novel species of the genus Chromobacterium, Chromobacterium subtsugae sp. nov.

Chromobacterium violaceum infection in Taiwan: a case report and literature review

Chromobacterium violaceum is a facultative anaerobic, Gram-negative bacillus which inhabits stagnant water in tropical and subtropical regions. We describe the case of an 80-year-old female patient with C. violaceum bacteremia due to traumatic wound infected by contaminated water and soil. She had persistent fever, hypotension and neutrophilic leukocytosis on admission. Two sets of blood cultures yielded C. violaceum. The patient was successfully treated with levofloxacin. Since the first case from Malaysia in 1927, about 150 cases have been reported in the world literature. To our knowledge, six other cases have been reported previously from Taiwan, including two children and four adults. Of the total of seven patients from Taiwan, four had a fatal outcome within several days, while the three survivors were apparently free of vital organ involvement. Although human infections caused by C. violaceum are rare, clinicians should be aware of this potentially fatal infection as part of the differential diagnosis of sepsis associated with a history of exposure to stagnant water.

Chromobacterium violaceum: a case report of an unusual bacterium causing puerperal sepsis

Human infections by Chromobacterium violaceum are rare. Till date 6 cases have been reported from southern and eastern parts of India. We report here a case of puerperal sepsis by C. violaceum, probably the first case from Eastern part of Orissa. The patient was successfully treated with amikacin and gatifloxacin.

Fatal septicaemia from Chromobacterium violaceum: case reports and review of the literature

Chromobacterium violaceum rarely causes infection in humans and its mechanism of pathogenicity is not well understood. Human infection carries a high mortality rate with a fulminating clinical progression. A high index of suspicion is required for diagnosis, and is based on recovering the organisms from blood cultures or other appropriate specimens. We present three cases of human infection managed in a tertiary referral hospital in Hong Kong with a review of the literature.

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.

Cell-cell influences on bacterial community development in aquatic biofilms

Dialysis tubing containing spent culture media, when placed in a lake, was colonized by a low diversity of bacteria, whereas abiotic controls had considerable diversity. Changes were seen in the presence and absence of acylated homoserine lactones, suggesting that these molecules and other factors may influence adherent-population composition.

[Chromobacteriosis in Ilhéus, Bahia: epidemiologic, clinical and laboratorial investigation]

In April/2004, a group of people traveled to a farm in a town in the south of Bahia and afterwards, three teenagers from the same family developed symptoms of severe septicemia and two died. The Health Department carried out an epidemiologic, clinical, laboratory and environmental investigation that resulted in the identification of Chromobacterium violaceum, in biological material from one of them, water and soil. This is the first report of the disease in Bahia State.

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.

Contrasting occurrence of Chromobacterium violaceum in tropical drinking water springs of Uganda

Occurrence of Chromobacterium violaceum in six protected drinking water springs in Uganda was investigated. C. violaceum showed a contrasting occurrence, which was independent of human impact as assessed by faecal pollution indicators. It was isolated from two springs (S1 and S2) that were located close to each other (3 km) but not in the rest. In S1 C. violaceum was continuously detected, in concentrations ranging from 6 to 270 cfu 100 ml(-1), while in S2 it was detected on only one sampling occasion. C. violaceum was never detected in the investigated upper soil layers (down to 15 cm) in the immediate surroundings (50 m radius) of the springs, despite continued isolation of faecal indicators. The results of the study indicate that C. violaceum may not be ubiquitous in spring water, but could occur in significant numbers in particular potable groundwaters as an autochthonous member.

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.

Genetic characterization of Chromobacterium isolates from black water environments in the Brazilian Amazon

AIMS

To isolate and to characterize the diversity of Chromobacterium violaceum from the Brazilian Amazon region.

METHODS AND RESULTS

Twenty-two isolates were obtained from the waters and banks of the river Negro, in the Brazilian Amazon. All isolates were able to grow in vitro at 44 degrees C and pH 4.0, but were adversely affected by temperatures below 15 degrees C, and unable to survive at 4 degrees C, properties that may be related to the adaptation to the ecosystem. The isolates were joined at a final level of similarity of only 13% in the rep-PCR analysis. The analysis of 16S rRNA genes resulted in three main groups clustered at a final level of similarity of 97% and only three isolates were clustered with the type strain. Similar data were obtained for the 23S rRNA gene.

CONCLUSIONS

A high level of genetic diversity was verified with indications that the Brazilian isolates would fit into at least two new clusters besides C. violaceum species.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results show remarkable bacterial adaptability and genetic diversity of C. violaceum in the Amazon region.

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.

Chromobacterium violaceum bacteremia: a case report

Chromobacterium violaceum is confined in tropical and subtropical regions, which can cause life-threatening disease. It is the only Chromobacterium species that is pathogenic to humans. Because of its rarity, clinicians often do not appreciate its importance when it is isolated. We report a fulminate fatal case of C. violaceum bacteremia in a 20-year-old male Taiwanese. The clinical manifestations were fever and abdominal pain, followed by shock and pulmonary septic embolism. Emergent laparotomy identified acute appendicitis with rupture. Flomoxef sodium was administered immediately. However, his condition deteriorated rapidly and he died within 48 h after the onset of illness. Two sets of blood culture yielded C. violaceum. Physicians should be aware of the occurrence of this infection in summer season.

Phagocyte NADPH oxidase, but not inducible nitric oxide synthase, is essential for early control of Burkholderia cepacia and chromobacterium violaceum infection in mice

Reactive oxygen and nitrogen intermediates have critical, partially overlapping roles in host defense against a variety of pathogens. Using mice deficient in generating phagocyte superoxide (p47(phox)(-/-)) and mice deficient in generating inducible nitric oxide synthase (iNOS(-/-)), we examined the roles of these reactive species in host defense against Burkholderia cepacia and Chromobacterium violaceum, organisms known to have unusual virulence in chronic granulomatous disease. Intraperitoneal B. cepacia challenge (4.0 x 10(3) to 4.0 x 10(5) organisms/mouse) resulted in mortality in all p47(phox)(-/-) mice, with the survival interval being inversely proportionate to the amount of inoculum. Pretreatment with gamma interferon did not affect survival. C. violaceum was strikingly virulent in p47(phox)(-/-) mice (the 50% lethal dose [LD(50)] was <13 organisms). iNOS(-/-) and wild-type mice were resistant to B. cepacia challenges of at least 10(6) organisms per mouse, and the LD(50) of C. violaceum was between 10(6) and 10(7) organisms per mouse. Consistent with the survival data, numbers of organisms in cultures of B. cepacia from multiple sites were higher for p47(phox)(-/-) mice than for iNOS(-/-) and wild-type mice at day 4 after challenge, but numbers of organisms for different B. cepacia strains varied. The recovery of C. violaceum was strikingly greater at 18 h after challenge for p47(phox)(-/-) mice than for iNOS(-/-) and wild-type mice, in which the organism burdens were virtually nil. In vitro, both B. cepacia and C. violaceum were sensitive to H(2)O(2) and to reactive nitrogen intermediates but the sensitivities of different strains varied significantly. Host defense against B. cepacia and C. violaceum is critically dependent in vivo on reactive oxygen intermediates, and these species are model organisms to further dissect host and pathogen interactions related to the generation and scavenging of microbicidal reactive intermediates.

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: a review of pharmacological and industiral perspectives

Violet-pigmented bacteria, which have been described since the end of the 19th century, are occasionally the causative agent of septicemia and sometimes cause fatal infection in human and animals. Bacteria, producing violet colonies due to the production of a nondiffusible pigment violacein, were classified as a redefined genus Chromobacterium. Chromobacterium violaceum is gram-negative, and saprophyte from soil and water is normally considered nonpathogenic to human, but is an opportunistic pathogen of extreme virulence for human and animals. The biosynthesis and biological activities of violacein and the diverse effects of this pigment have been studied. Besides violacein, C. violaceum produces other antibiotics, such as aerocyanidin and aerocavin, which exhibit in vitro activity against both gram-negative and gram-positive bacteria. 3,6-Dihydroxyindoxazene and Y-TO678h exhibit a selective activity against gram-negative bacteria. Arphamenine A and B, and FR901228, that enhanced immunoresponse, and potentiators of beta-lactam antibiotics and chelators such as ferrioxamine exhibit important clinical potential applications. Lipopolysaccharides and polyhydroxyesters together with several enzymes appear as important metabolites with biotechnological applications. Many of these metabolites were already studied at the genome level.

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.

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.

Fatal and non-fatal chromobacterial septicemia: report of two cases

Chromobacterium violaceum is frequently found in soil and water in tropical and subtropical regions. The organism rarely causes infection in humans, but is associated with a high mortality rate when it occurs. Septicemia associated with abscess in multiple organs such as the liver, skin, lungs, spleen, lymph nodes, and brain has been reported. We report on 2 patients with systemic infections with Chromobacterium violaceum. One presented with a fulminant course with multiple organ involvement and died 78 days later. The other presented with a milder course and survived after antibiotic therapy. In conclusion, infection with Chromobacterium violaceum is rare but its course is usually fulminant with high mortality especially in patients with sepsis and multiple organ involvement. We hope this report will provide additional information to physicians in the treatment of this disease.

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.

Chromobacterium violaceum infection in Brazil. A case report

We report the second case of infection with Chromobacterium violaceum that occurred in Brazil. A farm worker living in the State of São Paulo presented fever and severe abdominal pain for four days. At hospitalization the patient was in a toxemic state and had a distended and painful abdomen. Chest X-ray and abdominal ultrasound revealed bilateral pneumonia and hypoechoic areas in the liver. The patient developed failure of multiple organs and died a few hours later. Blood culture led to isolation of C. violaceum resistant to ampicillin and cephalosporins and sensitive to chloramphenicol, tetracyclin, aminoglicosydes, and ciprofloxacin. Autopsy revealed pulmonary microabscesses and multiple abscesses in the liver. The major features of this case are generally observed in infections by C. violaceum: rapid clinical course, multiple visceral abscesses, and high mortality. Because of the antimicrobial resistance profile of this Gram-negative bacillus, for appropriate empirical antibiotic therapy it is important to consider chromobacteriosis in the differential diagnosis of severe community infections in Brazil.

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.