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PubMed1998

Bartonella henselae neuroretinitis in cat scratch disease. Diagnosis, management, and sequelae.

OBJECTIVE: This study aimed to report the long-term outcomes of patients treated with an antibiotic drug combination for Bartonella henselae neuroretinitis. DESIGN: The study design was a retrospective case series. PARTICIPANTS: Seven consecutive patients with neuroretinitis and cat scratch disease participated. INTERVENTIONS: Patients underwent medical and ophthalmic evaluations. Blood cultures were obtained, and B. henselae antibody titers were measured. Tuberculosis, Lyme, toxoplasmosis, syphilis, and sarcoidosis were excluded. Patients received oral doxycycline 100 mg and rifampin 300 mg twice daily for 4 to 6 weeks and were observed for an average of 16 months (range, 10-24 months). Formal electrophysiologic testing was performed in three patients after resolution of neuroretinitis. MAIN OUTCOME MEASURES: The changes in ocular inflammation and visual function associated with treatment were recorded. Follow-up examinations and electrophysiologic testing documented sequelae. RESULTS: Patients presented following cat exposure with fever, malaise, and blurred vision. Decreased visual acuity (ranging from 20/40 to counting fingers) frequently was associated with dyschromatopsia and afferent pupillary defects. Ophthalmoscopic analysis showed signs of neuroretinitis, including nerve fiber layer hemorrhages, cotton-wool spots, multiple discrete lesions in the deep retina, and stellate macular exudates. B. henselae infection was confirmed with positive blood cultures or elevated immunofluorescent antibody titers or both. Therapy appeared to promote resolution of neuroretinitis, restoration of visual acuity, and clearance of bacteremia. After 1 to 2 years, two eyes had residual disc pallor, afferent pupillary defects, retinal pigmentary changes, and mildly decreased visual acuity. Electrophysiologic studies showed that when compared to the fellow eye, affected eyes had subnormal contrast sensitivity, abnormal color vision, and abnormal visually evoked potentials. Conversely, electroretinograms were normal in all subjects. CONCLUSIONS: B. henselae is a cause of neuroretinitis in cat scratch disease. Compared to historic cases, doxycycline and rifampin appeared to shorten the course of disease and hasten visual recovery. Long-term prognosis is good, but some individuals may acquire a mild postinfectious optic neuropathy.

Adult↗
PubMed2000

Parapharyngeal abscess due to cat-scratch disease.

The spectrum of illness attributed to cat-scratch disease (CSD) continues to expand. Although a common cause of cervical adenitis in children, CSD has not been associated as a cause of deep fascial space infections of the head and neck. We describe a child with extensive parapharyngeal adenitis and abscesses due to CSD confirmed by histological and serological evaluations.

Abscess↗
PubMedDate not supplied

[Atypical cat-scratch disease: a case report of splenic granulomatosis].

Generally cat-scratch disease is a benign inflammatory adenopathy. The Authors describe an atypical form of this disease, characterized by persistent fever and splenic granulomatosis requiring a diagnostic and therapeutic prolonged effort. They point out the important role of new immuno-fluorescent techniques to exactly identify the bacterium--Bartonella henselae--causing cat-scratch disease and suggest to include cat-scratch disease among the causes of unknown origin fever.

Anti-Bacterial Agents↗
PubMed2002

Studies on the growth of Bartonella henselae in the cat flea (Siphonaptera: Pulicidae).

Two out of three pools of cat fleas, Ctenocephalides felis (Bouche), that were fed Bartonella henselae-positive cat blood for 3 d and then bovine blood for 3 d, were polymerase chain reaction (PCR) positive for B. henselae. In a second experiment, three cats were inoculated with a streptomycin-resistant strain of B. henselae. After the cats were inoculated, caged cat fleas were fed on the cats during three different periods, and then pooled and transferred to noninfected recipient cats. In the first trial, the bacteria in the flea feces were below level of detection when the fleas were transferred from the infected cats to the recipient cat. After the fleas had fed on the recipient cat for 6 d, a bacteria level of 4.00 x 10(3) CFU/ mg was detected in the flea feces. Subsequently, the bacteria level increased for 4 d and then declined. In another experiment, the bacteria level in the flea feces was 1.80 x 10(3) CFU/mg at 2 h after collection and 3.33 x 10(2) CFU/mg at 72 h after collection. These data indicated that this strain of B. henselae can persist in flea feces in the environment for at least 3 d, and that B. henselae can multiply in the cat flea.

Animals↗
PubMedDate not supplied

[Peripheral lymphadenopathy in childhood--recommendations for diagnostic evaluation].

BACKGROUND: Enlargement of peripheral lymph nodes most commonly caused by a local inflammatory process is frequently seen in childhood. The aim of the present study was to analyze the most common causes of peripheral lymphadenopathy and to develop a simple algorithm for the primary diagnostic evaluation of peripheral lymph node enlargement in this age group. PATIENTS: Between April and September 1999 87 unselected children (median age: 5 1/2 years) with peripheral lymphadenopathy were referred to the Department of Pediatrics, University of Graz, for further investigation. RESULTS: EBV infection was diagnosed in 20 (23.0%) children. 19 (21.8%) patients had acute bacterial lymphadenitis. In 21 (24.1%) patients lymph node enlargement was classified as "post/parainfectious (viral)". Four patients each had toxoplasmosis and cat scratch disease. In 11 (12.6%) patients neither physical nor laboratory examinations revealed pathologic results. Among the remaining 8 children sarcoidosis and Hodgkin disease was diagnosed in one patient each. Small, soft, mobile, nontender, cervical, axillary or inguinal lymph nodes do not require further investigations. In case of enlarged, tender lymph nodes with overlying skin erythema and fever diagnostic evaluation should include complete blood count, erythrocyte sedimentation rate and/or c-reactive protein level, supplemented by appropriate antibody testing (EBV, CMV, Toxoplasma gondii, Bartonella henselae). Firm, enlarged, painless lymph nodes which are matted together and fixed to the skin or underlying tissues necessitate a more detailed diagnostic evaluation in order to exclude malignant or granulomatous diseases. CONCLUSIONS: Our study demonstrated that primary diagnostic evaluation of childhood peripheral lymphadenopathy is mainly based on clinical grounds. In most cases a small number of additionally performed laboratory tests allow to correctly identify the cause of the peripheral lymph node enlargement.

Adolescent↗
PubMed2004

Seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats.

OBJECTIVE: To compare seroprevalences of antibodies against Bartonella henselae and Toxoplasma gondii and fecal shedding of Cryptosporidium spp, Giardia spp, and Toxocara cati in feral and pet domestic cats. DESIGN: Prospective cross-sectional serologic and coprologic survey. ANIMALS: 100 feral cats and 76 pet domestic cats from Randolph County, NC. PROCEDURE: Blood and fecal samples were collected and tested. RESULTS: Percentages of feral cats seropositive for antibodies against B. henselae and T. gondii (93% and 63%, respectively) were significantly higher than percentages of pet cats (75% and 34%). Percentages of feral and pet cats with Cryptosporidium spp (7% of feral cats; 6% of pet cats), Giardia spp (6% of feral cats; 5% of pet cats), and T. cati ova (21% of feral cats; 18% of pet cats) in their feces were not significantly different between populations. Results of CBCs and serum biochemical analyses were not significantly different between feral and pet cats, except that feral cats had a significantly lower median PCV and significantly higher median neutrophil count. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that feral and pet cats had similar baseline health status, as reflected by results of hematologic and serum biochemical testing and similar prevalences of infection with Cryptosporidium spp, Giardia spp, and T. cati. Feral cats did have higher seroprevalences of antibodies against B. henselae and T. gondii than did pet cats, but this likely was related to greater exposure to vectors of these organisms.

Animals↗
PubMed1998

Construction of versatile high-level expression vectors for Bartonella henselae and the use of green fluorescent protein as a new expression marker.

Expression vectors suitable for directing high levels of protein synthesis in Bartonella henselae have been constructed based on the mobilisable broad-host-range (IncQ) plasmidpMMB206. They confer kanamycin resistance and feature the taclac (tac-lacUV5 in tandem) promoters in front of a polylinker followed by the rrnB transcriptional stop point. While expression of genes fused to the taclac promoter is constitutive in one vector, the lacIq gene carried by the other vector allows a controlled, IPTG-inducible gene expression. These vectors were tested by subcloning a mutated gfp gene coding for the green fluorescent protein (GFP) from Aequorea victoria into the multiple cloning site and introducing the resulting plasmids into Escherichia coli and B. henselae. GFP expression was determined by measuring fluorescence via flow cytometry or directly by immunoblotting. Compared to E. coli, expression of GFP in B. henselae was more tightly controlled by lacIq and resulted in much higher levels of both IPTG-induced and constitutive gene expression. In vitro infection of endothelial cells indicated that GFP expression does not adversely affect the interaction of B. henselae with host cells. These data demonstrate that (i) the established expression vectors are useful for directing controlled or constitutive high-level protein synthesis in B. henselae and (ii) that GFP is a valuable expression marker which may has important applications in studying the bacterial genetics and cellular interactions of this emerging human pathogen.

Bartonella henselae↗
PubMed2004

Multiplex real-time PCR for detection of anaplasma phagocytophilum and Borrelia burgdorferi.

A multiplex real-time PCR assay was developed for the simultaneous detection of Anaplasma phagocytophilum and Borrelia burgdorferi. The assay was tested on various Anaplasma, Borrelia, Erhlichia, and Rickettsia species, as well as on Bartonella henselae and Escherichia coli, and the assay was found to be highly specific for A. phagocytophilum and the Borrelia species tested (B. burgdorferi, B. parkeri, B. andersonii, and B. bissettii). The analytical sensitivity of the assay is comparable to that of previously described nested PCR assays (A. phagocytophilum, 16S rRNA; B. burgdorferi, fla gene), amplifying the equivalent of one-eighth of an A. phagocytophilum-infected cell and 50 borrelia spirochetes. The dynamic range of the assay for both A. phagocytophilum and B. burgdorferi was >/=4 logs of magnitude. Purified DNA from A. phagocytophilum and B. burgdorferi was spiked into DNA extracted from uninfected ticks and from negative control mouse and human bloods, and these background DNAs were shown to have no significant effect on sensitivity or specificity of the assay. The assay was tested on field-collected Ixodes scapularis ticks and shown to have 100% concordance compared to previously described non-probe-based PCR assays. To our knowledge, this is the first report of a real-time multiplex PCR assay that can be used for the simultaneous and rapid screening of samples for A. phagocytophilum and Borrelia species, two of the most common tick-borne infectious agents in the United States.

Anaplasma phagocytophilum↗
PubMed2006

The low seroprevalence of tick-transmitted agents of disease in dogs from southern Ontario and Quebec.

Infectious diseases caused by pathogens transmitted by ticks and other insect vectors are an important cause of morbidity and mortality in both dogs and humans throughout North America. The purpose of this study was to determine the seroprevalence of selected vector-transmitted pathogens in southern Ontario and Quebec. Samples submitted to the Vector Borne Disease Diagnostic Laboratory (VBDDL) at the North Carolina State University College of Veterinary Medicine were evaluated for antibodies to Ehrlichia canis, Anaplasma phagocytophilum, Babesia canis, Bartonella henselae, Borrelia burgdorferi, Bartonella vinsonii subspecies berkhoffii, and Rickettsia rickettsii. Information regarding breed and the city or province from which the sample originated was recorded; however, travel history was unknown for the majority of dogs. Overall seroprevalence to these tick-borne pathogens in southern Ontario and Quebec is low compared with most regions of the United States, suggesting that veterinarians in this region of Canada should pursue diagnostic evidence of infection in dogs with a travel history or prior residence in areas endemic for exposure to tick-borne infections.

Animals↗
PubMed2003

Characterization of the natural population of Bartonella henselae by multilocus sequence typing.

Investigations of the population genetics of Bartonella henselae have demonstrated a high level of diversity among strains, and the delineation of isolates into one of two subtypes, type I (Houston) and type II (Marseille), represented by specific 16S ribosomal DNA (rDNA) sequences, has long been considered the most significant genotypic division within the species. This belief is challenged by recent work suggesting a role for horizontal gene exchange in generating intraspecies diversity. We attempted to resolve this issue and extend exploration of the population structure of B. henselae by using multilocus sequence typing (MLST) to examine the distribution of polymorphisms within nine different genes in a sample of 37 human and feline isolates. MLST distinguished seven sequence types (STs) that resolved into three distinct lineages, suggesting a clonal population structure for the species, and support for these divisions was obtained by macrorestriction analysis using pulsed-field gel electrophoresis. The distribution of STs among isolates recovered from human infections was not random, and such isolates were significantly more often associated with one particular ST, lending further support to the suggestion that specific genotypes contribute disproportionately to the disease burden in humans. All but one isolate lay on lineages that bore the representative strain of either the Houston or Marseille subtype. However, the distribution of the two 16S rDNA alleles among the isolates was not entirely congruent with their lineage allocations, indicating that this is not a sensitive marker of the clonal divisions within the species. The inheritances of several of the genes studied could not be reconciled with one another, providing further evidence of horizontal gene transfer among B. henselae strains and suggesting that recombination has a role in shaping the genetic character of bartonellae.

Animals↗
PubMed2004

Latent infective endocarditis: epidemiology and clinical characteristics of patients with unsuspected endocarditis detected after elective valve replacement.

BACKGROUND: The diagnosis of infective endocarditis is usually made on the basis of clinical and laboratory criteria and may be confirmed by histologic examination or culture of excised valves. We tried to determine the incidence and significance of inflammatory changes in valves excised during operations for reasons other than infective endocarditis. METHODS: The charts and histopathology of all patients undergoing valve replacement during a 10-year period (1993-2002) were reviewed. A total of 868 patients underwent a total of 970 valve replacements during this period, of whom 11 patients (1.3%) were for endocarditis, with the remaining 857 (98.7%) for other indications. All excised valves were cultured and examined histologically for the presence of inflammatory infiltrates, vegetations, and microorganisms. RESULTS: In 8 of 857 patients (0.9%), the histologic examination unexpectedly demonstrated an infiltrate suggestive of endocarditis. Blood and valve cultures, and serologic tests for Mycoplasma, Chlamydia, Legionella, Q fever, Brucella, Rickettsiae, VDRL, and Bartonella were negative in all but 1 patient, who was found to have Q fever. All received a prolonged course of antibiotics. Six patients had an uneventful recovery; 1 had intramyocardial abscesses and expired during cardiac reoperation; and 1 had recurrent fever and dehiscence of the aortic and mitral valve prostheses and after two cardiac reoperations remains in severe heart failure. CONCLUSIONS: The presence of an unexpected inflammatory infiltrate in heart valves excised for reasons other than endocarditis may occur in 0.9% of such operations; these infiltrates could indicate presence of endocarditis. A microbial origin should be sought, and patients should receive empiric antibiotic treatment for endocarditis.

Adolescent↗
PubMed1998

Outbreak of epidemic typhus associated with trench fever in Burundi.

BACKGROUND: After a 12-year absence, epidemic typhus has re-emerged among the displaced population of Burundi. Following the outbreak of civil war in 1993, over 760000 people now inhabit refugee camps, under appalling conditions. A typhus outbreak occurred among prisoners in a jail in N'Gozi in 1995. At the time, the disease was not recognised, and was referred to as sutama. Reports of sutama among the civilian population date back to late 1995 and, in association with body-louse infestation, the disease has subsequently swept across the higher and colder regions of the country. METHODS: During a field study in February, 1997, 102 refugees with sutama underwent clinical examination and interview. Serum samples were collected and infesting body lice removed. Microbiological analysis included antibody estimations and specific PCRs aimed at diagnosis of Rickettsia prowezekii, Bartonella quintana, and Borrelia recurrentis. Between January and September, 1997, nationwide epidemiological data on the prevalence and distribution of sutama was obtained through liaison with local health services. A second field study in March, 1997, entailed the collection of further serum samples from suspected cases of sutama in different regions of Burundi. FINDINGS: Most of the 102 patients with sutama during initial assessment presented with manifestations similar to those previously described for typhus in Africa, though skin eruptions occurred in only 25 (25%) cases. Microbiological testing revealed evidence of R prowazeki infection in 76 (75%) patients, confirming that most cases of clinically-diagnosed sutama were epidemic typhus, and supporting the reliability of clinical diagnosis as a basis for the nationwide surveillance of the disease. Up to September, 1997, 45558 typhus cases were clinically diagnosed, most of which occurred in regions at an altitude of over 1500 m. Serological testing of 232 individuals from different regions of Burundi provided microbiological evidence to support clinical diagnoses in seven provinces, confirming the widespread nature of the outbreak. Serum from 13 of the original 102 patients and 19 (8%) of the 232 suspected cases had raised antibody titres against B quintana. A fatality rate of 15% among jail inmates fell to 0.5% after administration of a single dose of 200 mg doxycycline to suspected cases. INTERPRETATION: A gigantic outbreak of R prowazekii-induced typhus and B quintana-induced trench fever is continuing in Burundi. Transmission of both diseases to such a large number of people has followed a widespread epidemic of body-louse infestation. Diagnosis of typhus could be reliably made by means of clinical criteria, and the disease could be efficiently and easily treated by antibiotics. This epidemic highlights the appalling conditions in central-African refugee camps and the failure of public-health programmes to serve their inhabitants. Louse-associated disease remains a major health threat in this and other war-torn regions of the world.

Anti-Bacterial Agents↗
PubMed2006

Type IV secretion systems and their effectors in bacterial pathogenesis.

Type IV secretion systems (T4SSs) are membrane-associated transporter complexes used by various bacteria to deliver substrate molecules to a wide range of target cells. T4SSs are involved in horizontal DNA transfer to other bacteria and eukaryotic cells, in DNA uptake from or release into the extracellular milieu, in toxin secretion and in the injection of virulence factors into eukaryotic host target cells by several mammalian pathogens. Rapid progress has been made towards defining the structures and functions of T4SSs, identifying the translocated effector molecules and elucidating the mechanisms by which the effectors subvert eukaryotic cellular processes during infection. These findings have had an important impact on our understanding of how these pathogens manipulate host cell functions to trigger bacterial uptake, facilitate intracellular growth and suppress defence mechanisms, thus facilitating bacterial colonization and disease development.

Animals↗
PubMed2002

Epidemiology and impact of coinfections acquired from Ixodes ticks.

Ixodes scapularis and other ticks in the Ixodes ricinus complex may transmit multiple pathogens, but research on coinfections has been limited. Coinfections occur with varying frequency in ticks, but single infections are more common than dual infections. The proportion of I. scapularis or I. ricinus ticks coinfected with both Borrelia burgdorferi sensu lato and Anaplasma phagocytophila is generally low, ranging from < 1% to 6% in six geographic areas. A higher prevalence of tick coinfection (26%) has been reported in Westchester County, New York. Genetic variants of the human disease-causing strain of A. phagocytophila are present in some tick populations, and they may affect the risk of coinfection or clinical illness. The proportion of Ixodes ticks coinfected with B. burgdorferi and Babesia microti has ranged from 2% in New Jersey to 19% on Nantucket Island, Massachusetts. In humans, cross-sectional seroprevalence studies have found markers of dual infection in 9-26% of patients with a tick-borne infection, but such studies often fail to distinguish simultaneous coinfection from sequential infections. Several studies have prospectively assessed the occurrence of acute coinfection. Among patients with a confirmed tick-borne infection, coinfection rates as high as 39% have been reported. The most commonly recognized coinfection in most of the eastern United States is Lyme borreliosis (LB) and babesiosis, accounting for approximately 80% of coinfections. LB and human granulocytic ehrlichiosis coinfections are less common, occurring in 3-15% of patients with a tick-borne infection in Connecticut or Wisconsin. Studies of clinical outcomes suggest that patients with acute Babesia coinfection have more severe symptoms and a longer duration of illness than patients with LB alone, but the risk of spirochete dissemination is similar. Coinfections can modify the immune response and alter the severity of arthritis in animal models. Future coinfection research should focus on long-term clinical outcomes, the role of genetic variants, immunologic effects, and the potential role of Bartonella species as tick-borne pathogens.

Animals↗
PubMed2004

Study of genotypes and virB4 secretion gene of Bartonella henselae strains from patients with clinically defined cat scratch disease.

Bartonella henselae is the causative agent of cat scratch disease (CSD), which usually presents as a self-limiting lymphadenopathy. Occasionally, the bacteria will spread and be responsible for tissue and visceral involvement. Two B. henselae genotypes (genotypes I and II) have been described to be responsible for uncomplicated CSD on the basis of 16S rRNA sequence analysis. A type IV secretion system (T4SS) similar to the virulence-associated VirB system of Agrobacterium tumefaciens was recently identified in the B. henselae Houston-1 genotype I strain. We studied the correlations of the B. henselae genotypes with the clinical presentations and with the presence of T4SS. Isolates originated from CSD patients whose lymph nodes were prospectively analyzed. B. henselae genotype I was identified in 13 of 42 patients (30%). Among these, two teenage twins presented with hepatosplenic CSD and one immunocompetent adult presented with osteomyelitis. Genotype II was detected in 28 of 42 patients (67%), all of whom presented with uncomplicated CSD. The last patient was infected with both genotypes. T4SS was studied by PCR amplification of the virB4 gene. Amplification of virB4 codons 146 to 256, 273 to 357, and 480 to 537 enabled us to detect 66, 90, and 100% of the B. henselae isolates, respectively. Sequence analysis revealed sequence variations that correlated with genotype distribution. Our studies suggest that B. henselae genotype I strains harbor virB4 genes that are different from those harbored by genotype II strains and that genotype I strains might be more pathogenic.

Adolescent↗
PubMed2001

[Pseudotumoral presentation of cat scratch disease].

BACKGROUND: A frequent cause of chronic benign lymphadenopathy, cat-scratch disease (CSD) occurs mainly in children and young adults. Bartonella henselae is the agent responsible for CSD. The most common symptoms of the disease are regional lymphadenopathy and fever. Atypical forms occur in about 10% of patients; among them, CSD may initially present as a tumor. CASE REPORT: A 4-year-old child developed a 'tumor' of the arm with fever. The values of white blood cell count and CRP were normal. Ultrasonography, MRI and arteriography did not contribute to the diagnosis, which was established on histologic examination and serologic test for infection with B. henselae. The outcome was favorable with antibiotic treatment. CONCLUSION: In case of tumor of the limbs, cat-scratch disease should be searched for.

Anti-Bacterial Agents↗
PubMed2005

PCR detection of bacteria on cardiac valves of patients with treated bacterial endocarditis.

We used broad-range PCR amplification and sequencing to detect and identify bacterial DNA in 156 valves of patients treated for infective endocarditis (IE). Bacterial DNA was found more frequently in patients who underwent valve replacement while on antibiotic treatment for IE (60%) than in patients who had completed antibiotic treatment for IE (37%; P = 0.02). We found specific bacterial DNA in valves removed from 11 of 30 patients who had completed antibiotic treatment for IE. Six had no histological evidence of IE. The presence of DNA was significantly correlated with the presence of histologic lesions (P = 0.001) and with the presence of bacteria detected by Gram staining (P < 0.001). Bartonella and streptococci were detected for much longer after antibiotic treatment by PCR than other species (P = 0.047 and 0.04, respectively), and coagulase-negative staphylococci were detected for much shorter periods (P = 0.02). The finding that bacterial DNA was more likely to be detected in valves of patients with active IE than in patients who had completed antibiotic treatment for IE shows that bacterial DNA is cleared slowly. There was no significant correlation between the duration of antibiotic therapy and the presence of bacterial DNA in valves. Since the persistence of bacterial DNA in valves does not necessarily indicate the persistence of viable bacteria, the detection of bacterial DNA in valves from IE patients should be interpreted with caution, in particular in those patients with a past history of treated IE.

Adult↗
PubMed2006

[RNA amplification from low numbers of bacteria in human blood to solve low sensitivity problem of conventional PCR amplification].

Blood culture from a febrile patient is often unsuccessful when a number of bacteria is lower than 10 CFU/ml in circulation. Theoretically, PCR amplification of bacteria in this low bacterial level in human blood is beyond the sensitivity of PCR method. RNA based Amplification (NASBA) method is more sensitive than PCR base assay because living bacteria carries several hundred to thousand RNA molecules in a cell. Increasing evidences also revealed another problem that human blood stream is often contaminated with bacterial genome. This often cause false positive results and bring difficulty of the interpretation to determine causative agent. Direct DNA amplification should be limited to severe causative agent such as Haemophilus influenzae, Streptococcus pneumoniae, Neisseria meningitides, and etc. and also applied only for slow growing and fastidious pathogens such as mycoplasmae, chlamydiae, bartonellae, mycobacteria, and etc. Most cases blood culture should be carried out first and genetic amplification should be selected as a next step to detect pathogens from a blood culture bottle, because in these cases, patients are not in life threatening stages. These attempts also decrease the chance to detect circulating bacterial DNA fragment in blood stream.

Bacterial Infections↗