Bartonella henselae: A species of gram-negative bacteria that is the etiologic agent of bacillary angiomatosis (ANGIOMATOSIS, BACILLARY). This organism can also be a cause of CAT-SCRATCH DISEASE in immunocompetent patients.Bartonella: A genus of gram-negative bacteria characteristically appearing in chains of several segmenting organisms. It occurs in man and arthropod vectors and is found only in the Andes region of South America. This genus is the etiologic agent of human bartonellosis. The genus Rochalimaea, once considered a separate genus, has recently been combined with the genus Bartonella as a result of high levels of relatedness in 16S rRNA sequence data and DNA hybridization data.Bartonella Infections: Infections by the genus BARTONELLA. Bartonella bacilliformis can cause acute febrile anemia, designated Oroya fever, and a benign skin eruption, called verruga peruana. BARTONELLA QUINTANA causes TRENCH FEVER, while BARTONELLA HENSELAE is the etiologic agent of bacillary angiomatosis (ANGIOMATOSIS, BACILLARY) and is also one of the causes of CAT-SCRATCH DISEASE in immunocompetent patients.Cat-Scratch Disease: A self-limiting bacterial infection of the regional lymph nodes caused by AFIPIA felis, a gram-negative bacterium recently identified by the Centers for Disease Control and Prevention and by BARTONELLA HENSELAE. It usually arises one or more weeks following a feline scratch, with raised inflammatory nodules at the site of the scratch being the primary symptom.Angiomatosis, Bacillary: A reactive vascular proliferation that is characterized by the multiple tumor-like lesions in skin, bone, brain, and other organs. Bacillary angiomatosis is caused by infection with gram-negative Bartonella bacilli (such as BARTONELLA HENSELAE), and is often seen in AIDS patients and other IMMUNOCOMPROMISED HOSTS.Bartonella quintana: A species of gram-negative bacteria in which man is the primary host and the human body louse, Pediculus humanus, the principal vector. It is the etiological agent of TRENCH FEVER.Cat Diseases: Diseases of the domestic cat (Felis catus or F. domesticus). This term does not include diseases of the so-called big cats such as CHEETAHS; LIONS; tigers, cougars, panthers, leopards, and other Felidae for which the heading CARNIVORA is used.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)Trench Fever: An intermittent fever characterized by intervals of chills, fever, and splenomegaly each of which may last as long as 40 hours. It is caused by BARTONELLA QUINTANA and transmitted by the human louse.Bartonella bacilliformis: The type species of the genus BARTONELLA, a gram-negative bacteria found in humans. It is found in the mountain valleys of Peru, Ecuador, and Southwest Columbia where the sandfly (see PHLEBOTOMUS) vector is present. It causes OROYA FEVER and VERRUGA PERUANA.Siphonaptera: An order of parasitic, blood-sucking, wingless INSECTS with the common name of fleas.Peliosis Hepatis: A vascular disease of the LIVER characterized by the occurrence of multiple blood-filled CYSTS or cavities. The cysts are lined with ENDOTHELIAL CELLS; the cavities lined with hepatic parenchymal cells (HEPATOCYTES). Peliosis hepatis has been associated with use of anabolic steroids (ANABOLIC AGENTS) and certain drugs.Bartonellaceae: A family of small gram-negative bacteria whose organisms are parasites of erythrocytes in man and other vertebrates and the etiologic agents of several diseases.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Ctenocephalides: A genus of FLEAS in the family Pulicidae. It includes the cat flea (Ctenocephalides felis), one of the most common species on earth.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Grenada: An island of the West Indies. Its capital is St. George's. It was discovered in 1498 by Columbus who called it Concepcion. It was held at different times by the French and the British during the 18th century. The British suppressed a native uprising in 1795. It was an associate state of Great Britain 1967-74 but became an independent nation within the British Commonwealth in 1974. The original name referred to the Feast of the Immaculate Conception but it was later renamed for the Spanish kingdom of Granada. (From Webster's New Geographical Dictionary, 1988, p467 & Room, Brewer's Dictionary of Names, 1992, p219)Bacteremia: The presence of viable bacteria circulating in the blood. Fever, chills, tachycardia, and tachypnea are common acute manifestations of bacteremia. The majority of cases are seen in already hospitalized patients, most of whom have underlying diseases or procedures which render their bloodstreams susceptible to invasion.Disease Reservoirs: Animate or inanimate sources which normally harbor disease-causing organisms and thus serve as potential sources of disease outbreaks. Reservoirs are distinguished from vectors (DISEASE VECTORS) and carriers, which are agents of disease transmission rather than continuing sources of potential disease outbreaks.Lymphatic Diseases: Diseases of LYMPH; LYMPH NODES; or LYMPHATIC VESSELS.RNA, Ribosomal, 16S: Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.Ectoparasitic Infestations: Infestations by PARASITES which live on, or burrow into, the surface of their host's EPIDERMIS. Most ectoparasites are ARTHROPODS.Endocarditis, Bacterial: Inflammation of the ENDOCARDIUM caused by BACTERIA that entered the bloodstream. The strains of bacteria vary with predisposing factors, such as CONGENITAL HEART DEFECTS; HEART VALVE DISEASES; HEART VALVE PROSTHESIS IMPLANTATION; or intravenous drug use.Seroepidemiologic Studies: EPIDEMIOLOGIC STUDIES based on the detection through serological testing of characteristic change in the serum level of specific ANTIBODIES. Latent subclinical infections and carrier states can thus be detected in addition to clinically overt cases.Fluorescent Antibody Technique, Indirect: A form of fluorescent antibody technique commonly used to detect serum antibodies and immune complexes in tissues and microorganisms in specimens from patients with infectious diseases. The technique involves formation of an antigen-antibody complex which is labeled with fluorescein-conjugated anti-immunoglobulin antibody. (From Bennington, Saunders Dictionary & Encyclopedia of Laboratory Medicine and Technology, 1984)Rickettsieae: A tribe of gram-negative bacteria of the family RICKETTSIACEAE whose organisms are found in arthropods and are pathogenic for man and certain other vertebrate hosts.Panuveitis: Inflammation in which both the anterior and posterior segments of the uvea are involved and a specific focus is not apparent. It is often severe and extensive and a serious threat to vision. Causes include systemic diseases such as tuberculosis, sarcoidosis, and syphilis, as well as malignancies. The intermediate segment of the eye is not involved.Leukemia, Feline: A neoplastic disease of cats frequently associated with feline leukemia virus infection.Rickettsiaceae: A family of small, gram-negative organisms, often parasitic in humans and other animals, causing diseases that may be transmitted by invertebrate vectors.Tick-Borne Diseases: Bacterial, viral, or parasitic diseases transmitted to humans and animals by the bite of infected ticks. The families Ixodidae and Argasidae contain many bloodsucking species that are important pests of man and domestic birds and mammals and probably exceed all other arthropods in the number and variety of disease agents they transmit. Many of the tick-borne diseases are zoonotic.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.DNA, Ribosomal Spacer: The intergenic DNA segments that are between the ribosomal RNA genes (internal transcribed spacers) and between the tandemly repeated units of rDNA (external transcribed spacers and nontranscribed spacers).Immunocompetence: The ability of lymphoid cells to mount a humoral or cellular immune response when challenged by antigen.