Cat scratch disease in the United States: an analysis of three national databases

A case of hepatosplenic cat scratch disease with hemophagocytic lymphohistiocytosis

Cat scratch disease (CSD) is associated with Bartonella henselae (B. henselae) infection caused by cat scratches or bites. It typically presents with lymphadenitis and fever. However, there are atypical cases such as hepatosplenic CSD, which presents with specific lesions in the liver and spleen. Hemophagocytic lymphohistiocytosis (HLH) is a rare and severe multisystem disorder triggered by infections, cancers, or autoimmune diseases. We experienced a rare case of hepatosplenic CSD with HLH in a non-immunocompromised adult. A 78-year-old woman complained of fever and fatigue. Laboratory tests revealed anemia and liver dysfunction; abdominal contrast-enhanced computed tomography (CT) revealed splenomegaly and nodular hypodense areas in the spleen. In addition, the levels of ferritin and serum soluble IL-2R were markedly elevated, so clinical diagnosis of HLH was made. Positron emission tomography/CT revealed diffuse fluorodeoxyglucose uptake in the liver and spleen suggesting malignant lymphoma, while the pathological findings from liver biopsy suggested infectious diseases. Although she had no cat bites and scratches, she had many cats; therefore, serum B. henselae antibody titers were measured. The B. henselae IgG and IgM titer were 1:128 and 1:20; thus, she was diagnosed with hepatosplenic CSD. Patients with hepatosplenic nodular lesions and contact with cats should be considered for this disease.

A Case Series of Cat-Scratch Disease with Ocular Manifestations: Clinical Findings and Treatment Approach

Objectives

To present the clinical and demographic characteristics, imaging findings, diagnosis and treatment approach in cases of cat scratch disease (CSD) with ocular involvement.

Materials and Methods

The records of 19 patients followed-up and treated between 2010 and 2020, including detailed ophthalmological examinations, imaging findings, and treatment approach, were evaluated retrospectively.

Results

Twenty-three eyes of 19 patients, 7 female (37%) and 12 male (63%), were included in the study. The mean age was 34.1±13.3 (range: 11-56) years, and the mean follow-up duration was 12.6±18.0 (range: 1-81) months. Unilateral involvement was observed in 15 cases (79%). Cat contact was reported in 14 cases (74%). In 6 cases (32%), flu-like symptoms were present before the ocular complaints. The mean visual acuity (VA) at presentation was 0.42±0.36 (range: 0.001-1.0). Anterior uveitis was observed in 3 eyes (13%). Posterior segment findings included neuroretinitis in 14 (61%), superficial retinal infiltrate(s) in 8 (35%), papillitis in 3 (13%), branch retinal artery occlusion in 2 (8%), and cilioretinal artery occlusion in 1 (4%) of the eyes. All cases were positive for Bartonella henselae immunglobulin (Ig)M and/or IgG. Systemic antibiotic therapy was administered to all patients. Intravenous pulse or oral corticosteroids were given, especially in cases with optic disc involvement. The mean final VA was 0.80±0.25 (range: 0.01-1.0).

Conclusion

CSD may present with different ocular involvement patterns. Apart from the classical neuroretinitis and macular star appearance, patients may present with isolated optic disc edema, branch retinal artery occlusion, and retinal infiltrations. In such patients, cat contact history and Bartonella serology should be evaluated to differentiate CSD.

Abnormal Presentation of Bartonella henselae Encephalopathy in a Pediatric Patient

Cat scratch disease (CSD) is a zoonotic infection caused by the transmission of gram-negative bacteria Bartonella henselae through a scratch or bite of a feline carrying B. henselae-infected fleas. CSD often presents clinically as a self-limited flu-like infection with painful regional lymphadenopathy appearing one to two weeks following initial transmission. However, a growing body of literature highlights abnormal presentations of Bartonella infections within the pediatric population. In this case report, we describe an atypical presentation of a B. henselae infection in an 11-year-old female with seizures, prolonged encephalopathy, agitation, and truncal instability. With an atypical presentation, a delay in diagnosis can result in potentially permanent organ damage, particularly as traditional empiric antibiotics fail to cover Bartonella infections. As such, proper treatment and complete resolution of symptoms require astute clinical recognition to make the correct diagnosis promptly.

Cat scratch disease: What to do with the cat?

Purpose

Cat scratch disease (CSD) frequently has ophthalmologic manifestations. The ophthalmologist's approach to treating neuroretinitis is familiar, but few eye care providers are comfortable answering the next question of “what do I do with my cat?” Published guidelines are often vague in answering the complexities of real-life conundrums that can lead patients and their doctors to believe that risk mitigation should involve removal of the animal. Here, we present demonstrative scenarios informed by clinical practice and provide updated recommendations.

Observations

A 10-year-old boy presented with reduced vision in the right eye. Funduscopic examination identified optic nerve head edema with subretinal fluid, and a macular star developed one week later, consistent with the diagnosis of neuroretinitis. Serology confirmed Bartonella henselae antibodies and a diagnosis of CSD. The father disclosed that the family has recently adopted three kittens, who have scratched the boy and the patient's younger sister. The physician and patient's family find themselves at a loss regarding best practices for what should be done with the kittens.

Conclusions and Importance

B. henselae has been detected in a variety of mammals and can be transmitted via vectors such as fleas. Even well-appearing animals can transmit the bacteria, months to years after their initial infection. Symptoms, clinical and laboratory findings will depend on bacterial load and strain virulence, as well as the physiological/immunological status of the host, with people at the extremes of age and the immunocompromised being at greater disease risk. Flea control is crucial to minimize transmission risk. Our veterinary expert (EBB) recommends testing (with serology and PCR) and treating infected animals (with doxycycline and a quinolone). Patients should be counseled to speak with their pets’ veterinarian. When addressing the concerns of our CSD patients in clinical practice, ophthalmologists should be aware of the strategies for minimizing Bartonella transmission risk, and cognizant of the One Health approach for managing zoonoses.

Prevalence of selected pathogens in ectoparasites from free-roaming domestic cats in the southern Great Plains of the United States

Rickettsia sp. and Bartonella sp. were detected in ectoparasites of free-roaming domestic cats (Felis catus) from a trap-neuter-release program in central Oklahoma during January and February 2020. We used polymerase chain reaction and sequencing to identify fleas containing DNA of five different pathogens: Rickettsia felis (84%), 'Candidatus R. andeanae' (8%), Bartonella henselae (32%), Bartonella clarridgeiae (36%), and Bartonella sp. (8%). Co-infections with R. felis with three Bartonella species were identified. One tick was positive for R. felis, one flea was positive for 'Candidatus R. andeanae' and one ear mite was positive for a Bartonella species. These results highlight the need for more focus on free-roaming domestic cats and their ectoparasites in the Great Plains region.

A Review of Bartonella Infections in California-Implications for Public and Veterinary Health

Bartonella are vector-transmitted, intracellular bacteria that infect a wide variety of blood-feeding arthropods and their vertebrate hosts. In California, more than 13 species of Bartonella have been described from companion animals, livestock, and wildlife, of which four have been associated with human disease. Infections in humans cause a range of symptoms from relatively mild to severe, especially in immunocompromised individuals. Exposure to infected domestic animals and wildlife, and their ectoparasites, may increase the risk of cross-species transmission. The objective of this review was to compile and summarize published materials on human and animal Bartonella infections in California. Medical and veterinary case reports of bartonellosis were highlighted in an effort to increase the awareness of this poorly understood and potentially under-recognized disease among healthcare professionals and veterinarians.

Serological and Molecular Detection of Bartonella henselae in Cats and Humans From Egypt: Current Status and Zoonotic Implications

Bartonellosis is a vector-borne zoonotic disease caused by the intracellular bacterium of genus Bartonella. The disease has a worldwide distribution and cats represent the major reservoir of this disease. Despite its global distribution, very limited previous studies have investigated the occurrence of bartonellosis in cats and their owners in Egypt. In an endeavor to explore this topic, we investigated the occurrence of Bartonella henselae (B. henselae) infection in 225 samples (blood, saliva, and claw) obtained from 75 healthy cats in Upper Egypt. These samples were routinely obtained during veterinary clinic visits. This study also involved an examination of 100 humans, including cat owners and people with a history of contact with cats. Attempted isolation and identification of B. henselae in cats were also performed. Furthermore, PCR was performed for molecular identification of B. henselae in blood samples from cats. Meanwhile, an immunofluorescent assay was performed to study the seroprevalence of B. henselae infection in humans. In this study, B. henselae could not be isolated from any of the examined blood, saliva, or claw samples from cats. Interestingly, B. henselae was identified molecularly in 8% (6/75) of blood samples from cats. The seroprevalence of B. henselae in humans was 46% and its occurrence was higher in females (46.6%) than in males (41.7%) (P = 0.748). B. henselae infection was higher among cat owners [51.4% (19/37)] than among people with a history of contact with cats [42.9% (27/63)] (P = 0.410). Infection was higher in rural regions [79.5% (31/39)] than in urban regions [24.6% (15/61)] (P < 0.001). Collectively, this data provide interesting baseline information about the occurrence of B. henselae in cats and humans in Upper Egypt, which reflects the potential zoonotic transmission of this bacterium. Future study is mandatory to explore the occurrence of B. henselae in major reservoirs in Egypt.

The Clinical Profile of Cat-Scratch Disease’s Neuro-Ophthalmological Effects

Cat-scratch disease is an illness caused by Bartonella henselae that occurs as a result of contact with an infected kitten or dog, such as a bite or scratch. It is more prevalent in children and young adults, as well as immunocompromised individuals. There are limited publications examining the features of CSD in patients. As such, the purpose of this research was to assess the clinical neuro-ophthalmological consequences of CSD reported in the literature. Among the ophthalmologic disorders caused by cat-scratch disease in humans, Parinaud oculoglandular syndrome, uveitis, vitritis, retinitis, retinochoroiditis and optic neuritis are the most prevalent. The neurological disorders caused by cat-scratch disease in humans include encephalopathy, transverse myelitis, radiculitis, and cerebellar ataxia. The current review addresses the neuro-ophthalmological clinical manifestations of cat-scratch disease, as described in papers published over the last four decades (1980–2022). All the data gathered were obtained from PubMed, Medline and Google Scholar. The current descriptive review summarizes the most-often-encountered clinical symptomatology in instances of cat-scratch disease with neurological and ocular invasion. Thus, the purpose of this review is to increase knowledge of cat-scratch disease’s neuro-ophthalmological manifestations.

Exploring the seasonal and regional features of cat-scratch disease on the basis of anti-Bartonella henselae IgM/IgG positive rates in Japan

OBJECTIVES

This study aimed to explore the seasonal and regional features of cat-scratch disease (CSD) based on 15-years of test results for anti-Bartonella henselae IgG and IgM by immunofluorescence assay (IFA) performed as a laboratory specialized in diagnostic testing of CSD in Japan. A literature search was performed to put our findings in perspective.

METHODS

A total of 956 sera from patients suspected of CSD were submitted to our laboratory from nationwide. Seasonal changes in the monthly positive rates of IgG/IgM antibodies and regional distribution of the test specimens were analyzed.

RESULTS

The monthly positive rates of anti-B. henselae IFA of IgG and IgM were both significantly high between September and January and low between March and July. The seasonal pattern observed in this study was similar to the ones reported from US and France, which were analyzed from a clinical database (monthly incidence of CSD diagnosis) or from monthly positive rates of either B. henselae PCR or anti-B. henselae IFA. However, fluctuations in the IFA monthly positive rates in this study were more pronounced than other reports. Regarding regionality, the test specimens submitted to us for IFA were prominently more from southwestern areas than from northern/middle-northern areas of Japan. The distribution coincided well with the regional distribution of CSD case reports and with a known regional prevalence of Bartonella-species bacteremia among pet cats in Japan.

CONCLUSION

These epidemiological features in Japan are of relevance in the clinical diagnoses of CSD.

Isolated hepatosplenic abscess from cat scratch disease in a patient with HIV

Bartonella henselae infection, or cat scratch disease, typically is a self-limiting disease presenting as lymphadenopathy and fever after a bite or scratch from a cat. The most commonly reported presentation in immunocompromised patients includes bacillary angiomatosis and peliosis hepatitis, which resemble Kaposi's sarcoma. Isolated hepatosplenic abscess without diffuse lymphadenopathy or vasoproliferative disease is seldom reported in adult immunocompromised patients. Although several advances have been made in identifying the organism and antibodies with serological tests, biopsy, and polymerase chain reaction, there is little information about treatment. We report a case of an isolated hepatosplenic abscess without lymphadenopathy or vasoproliferative disease caused by B. henselae in an adult immunocompromised patient with HIV.

Atypical Manifestations of Cat-Scratch Disease, United States, 2005-2014

Atypical manifestations that can be severe and difficult to diagnosis develop in 5%-20% of patients with cat-scratch disease. To clarify the epidemiology of atypical cat-scratch disease in the United States, we analyzed data from the 2005-2014 MarketScan national health insurance claims databases by using the International Classification of Diseases, 9th Revision, Clinical Modification, codes for cat-scratch disease and selected atypical manifestations: retinitis/neuroretinitis, conjunctivitis, neuritis, encephalitis, hepatosplenic disease, osteomyelitis, erythema nodosum, and endocarditis. Atypical cat-scratch disease accounted for 1.5% of all cases, resulting in an average annual incidence of 0.7 cases/100,000 population. Atypical cat-scratch disease was associated with increased risk for hospitalization (risk ratios 8.77, 95% CI 6.56-11.72) and occurred most often in female patients 10-14 years of age. Ocular (48.7%), hepatosplenic (24.6%), and neurologic (13.8%) manifestations were most common among patients. A more comprehensive understanding of atypical cat-scratch disease can improve patient diagnosis and potentially elucidate pathophysiology of the disease.

Cat Scratch Disease Presenting as Fever of Unknown Origin Is a Unique Clinical Syndrome

BACKGROUND

Fever of unknown origin (FUO) is a rare manifestation of cat scratch disease (CSD). Data regarding CSD-associated FUO (CSD-FUO), particularly in adults, are limited. We aimed to study disease manifestations and long-term clinical outcome.

METHODS

A national CSD surveillance study has been conducted in Israel since 1991. Data are obtained using questionnaires, review of medical records, and telephone interviews. FUO was defined as fever of ≥14 days without an identifiable cause. CSD-FUO patients were identified in the 2004-2017 CSD national registry. Follow-up included outpatient clinic visits and telephone/e-mail surveys.

RESULTS

The study included 66 CSD-FUO patients. Median age was 35.5 years (range, 3-88). Median fever duration was 4 weeks (range, 2-9). Relapsing fever pattern was reported in 52% of patients, weight loss in 57%, and night sweats in 48%. Involvement of ≥1 organs occurred in 59% of patients; hepatosplenic space-occupying lesions (35%), abdominal/mediastinal lymphadenopathy (20%), ocular disease (18%), and multifocal osteomyelitis (6%) were the most common. Malignancy, particularly lymphoma, was the initial radiological interpretation in 21% of patients; 32% underwent invasive diagnostic procedures. Of the 59 patients available for follow-up (median duration, 31 weeks; range, 4-445), 95% had complete recovery; 3 patients remained with ocular sequelae.

CONCLUSION

This is the first attempt to characterize CSD-FUO as a unique syndrome that may be severe and debilitating and often mimics malignancy. Relapsing fever is a common clinical phenotype. Multiorgan involvement is common. Recovery was complete in all patients except in those with ocular disease.

What Is in a Cat Scratch? Growth of Bartonella henselae in a Biofilm

Bartonella henselae (B. henselae) is a gram-negative bacterium that causes cat scratch disease, bacteremia, and endocarditis, as well as other clinical presentations. B. henselae has been shown to form a biofilm in vitro that likely plays a role in the establishment and persistence of the bacterium in the host. Biofilms are also known to form in the cat flea vector; hence, the ability of this bacterium to form a biofilm has broad biological significance. The release of B. henselae from a biofilm niche appears to be important in disease persistence and relapse in the vertebrate host but also in transmission by the cat flea vector. It has been shown that the BadA adhesin of B. henselae is critical for adherence and biofilm formation. Thus, the upregulation of badA is important in initiating biofilm formation, and down-regulation is important in the release of the bacterium from the biofilm. We summarize the current knowledge of biofilm formation in Bartonella species and the role of BadA in biofilm formation. We discuss the evidence that defines possible mechanisms for the regulation of the genes required for biofilm formation. We further describe the regulation of those genes in the conditions that mimic both the arthropod vector and the mammalian host for B. henselae. The treatment for persistent B. henselae infection remains a challenge; hence, a better understanding of the mechanisms by which this bacterium persists in its host is critical to inform future efforts to develop drugs to treat such infections.

Clinical profile and visual outcome of intraocular inflammation associated with cat-scratch disease in Japanese patients

PURPOSE

To evaluate intraocular inflammation in Japanese patients with cat-scratch disease (CSD).

STUDY DESIGN

Retrospective clinical chart review.

PATIENTS AND METHODS

The cases of 15 consecutive patients (19 affected eyes) in Kochi Prefecture, Japan who were serologically positive for Bartonella henselae or Bartonella quintana infection in association with intraocular inflammation were reviewed. The clinical manifestations, ocular complications, and treatment modalities were recorded. The clinical charts and photographic records were also reviewed for evidence of optic disc lesions, macular star, foci of chorioretinitis, and other findings.

RESULTS

Thirteen patients reported fever before or at the time of the initial presentation. Ten of 11 patients with decreased visual acuity manifested neuroretinitis, and the remaining patient showed retinochoroiditis with macular involvement. One patient with a visual field defect manifested branch retinal artery occlusion. Three patients without visual disturbance presented with fever of unknown cause. Discrete white retinal or retinochoroidal lesions were the most common findings (84% of eyes, 87% of patients), followed by retinal hemorrhage (63% of eyes, 80% of patients), optic disc lesions (63% of eyes, 73% of patients), serous retinal detachment (53% of eyes, 67% of patients), and macular star (47% of eyes, 60% of patients).

CONCLUSION

White retinal or retinochoroidal foci were the most common ocular posterior segment manifestations of CSD in this patient population. A diagnosis of CSD should be suspected in patients with fever and chorioretinal white spots, and the absence of neuroretinitis or macular star does not exclude the possibility of intraocular inflammation in CSD.

Rare Diseases of the Salivary Glands and of Facial Nerve

Salivary gland diseases are rare. In the European Union (EU) a disease is considered to be rare if not more than 5 of 10,000 people are affected by it. According to estimates in Germany are about 4 million people with a rare disease. In the EU are about 30 million people with rare diseases [1]. In the present work most of the described diseases of salivary glands and of the facial nerve fall in this category. They form a very heterogeneous group whose treatment takes place mainly in specialized centers. Still, it is essential for the otolaryngologist to identify and to diagnose these diseases in order to initiate the right therapeutic steps. The work is a compilation of innate andacquired rare salivary gland disorders and of rare facial nerve disorders. The etiologies of inflammatory diseases, autoimmune disorders and tumors are taken into account. For the individual topics, the current literature, if available, was evaluated and turned into summarized facts. In this context the development of new processes, diagnostics, imaging and therapy are considered. Genetic backgrounds of salivary gland tumors and the trends in the treatment of tumorous lesions of the facial nerve are picked up. Furthermore, also rare diseases of the salivary glands in childhood are described. Some of them can occur in adults as well, but differ in frequency and symptoms. Due to the rarity of these diseases, it is recommended to tread these in centers with special expertise for it. Finally, the difficulties of initiation of studies and the problems of establishing disease registries concerning salivary gland disorders are discussed. This is very relevant because these pathologies are comparatively seldom.

Clinical Manifestations Associated with Bartonella henselae Infection in a Tropical Region

Bartonella henselae is a zoonotic Gram-negative Bacillus associated with self-limited regional lymphadenopathy. In recent decades, an expanding spectrum of clinical manifestations has been described, in part, due to improved diagnostics. However, updated epidemiological data are sparse. We retrospectively reviewed the clinical features of 31 patients with B. henselae infection over 15 years from 2005 to 2019, in the tropical Top End of Australia. Our annual disease incidence of 1.3 cases per 100,000 population is lower than that in the national database surveillances in the United States, but the hospitalization incidence of 0.9 per 100,000 population in our region is higher than those reported in the literature, with an average length of stay of 9 days. Patients were more commonly male, aboriginal, and aged less than 14 years (median age: 7 years), living in a rural setting with presentation during our monsoon season. The disease spectrum included lymph node disease (74%), organ peliosis, endocarditis, cutaneous lesions, parapharyngeal abscess, parotitis, and neurologic and ocular syndromes. Lymph node disease was far commoner in children than the more serious systemic B. henselae infections associated with adults (P = 0.074). Although no deaths were reported, significant morbidities were observed. Two endocarditis cases presented with glomerulonephritis, and hematological and neurological features mimicking vasculitis, and consequently received immunosuppressants. One case was only diagnosed after representation with serial embolic strokes. Given the heterogeneity of disease manifestations with nonspecific symptoms and significant consequences, a timely and accurate diagnosis is needed to avoid unnecessary treatments or interventions.

Epidemiological of cat scratch disease among inpatients in the Spanish health system (1997-2015)

Cat scratch disease, whose causative agent is Bartonella henselae, is an anthropozoonosis with a worldwide distribution that causes significant public health problems. Although it is an endemic disease in Spain, the available data are very limited. The aim of our study was to describe cat scratch disease inpatients in the National Health System (NHS) of Spain. This was a retrospective descriptive study using the minimum basic data set (CMBD in Spanish) in patients admitted to hospitals of the NHS between 1997 and 2015 with a diagnosis of cat scratch disease (ICD-9: 078.3). We found 781 hospitalized patients diagnosed with cat scratch disease. The mean age (± SD) was 30.7 ± 25.3 years old. The male/female ratio was 1.1:1. The incidence rate over the study period was 0.93 (95% CI, 0.86-0.99) cases per million person-years. The incidence rate in men was 0.98 cases per million person-years and that in women was 0.88 cases per million person-years. The cases were more frequent from September to January. A total of 652 (83.5%) cases were urgent hospital admissions. The average hospital stay was 8.4 ± 8.9 days. The overall lethality rate of the cohort was 1.3%. We have demonstrated that CSD causes a substantial burden of disease in Spain, affecting both adult and pediatric patients with a stable incidence rate. Our data suggest that CSD is benign and self-limited, with low mortality, and its incidence is possibly underestimated. Finally, there is a need for a common national strategy for data collection, monitoring, and reporting, which would facilitate a more accurate picture and the design of more strategic control measures. Hospital discharge records (HDRs) could be a good database for the epidemiological analysis of the hospital management of CSD.

Disseminated Cat Scratch Disease in Pediatric Patients in Hawai'i

Cat scratch disease is known to be a generally benign, self-resolving illness associated with non-specific symptoms, including lymphadenopathy, fever, fatigue, anorexia, and headaches. However, it can also cause disseminated disease with a wide range of manifestations, including liver and spleen microabscesses, osteomyelitis, encephalitis, and uveitis. Eighteen pediatric cases of disseminated cat scratch disease at a single center in Hawai'i are described. This case series emphasizes the importance of disease recognition and use of appropriate diagnostic tools and disease management. The disease burden of pediatric patients with disseminated cat scratch disease in the state of Hawai'i has a high incidence and should be considered in pediatric patients with prolonged febrile illnesses.

Effect of different drugs and drug combinations on killing stationary phase and biofilms recovered cells of Bartonella henselae in vitro

BACKGROUND

Bartonella henselae is a Gram-negative bacterium transmitted to humans by a scratch from cat in the presence of ectoparasites. Humans infected with B. henselae can result in various clinical diseases including local lymphadenopathy and more serious systemic disease such as persistent bacteremia and endocarditis. The current treatment of persistent B. henselae infections is not very effective and remains a challenge. To find more effective treatments for persistent and biofilm Bartonella infections, in this study, we evaluated a panel of drugs and drug combinations based on the current treatment and also promising hits identified from a recent drug screen against stationary phase and biofilm recovered cells of B. henselae.

RESULTS

We evaluated 14 antibiotics and 25 antibiotic combinations for activity against stationary phase B. henselae (all antibiotics were at 5 μg/ml) and found that ciprofloxacin, gentamicin, and nitrofurantoin were the most active agents, while clofazimine and miconazole had poor activity. Drug combinations azithromycin/ciprofloxacin, azithromycin/methylene blue, rifampin/ciprofloxacin, and rifampin/methylene blue could rapidly kill stationary phase B. henselae with no detectable CFU after 1-day exposure. Methylene blue and rifampin were the most active agents against the biofilm B. henselae after 6 days of drug exposure. Antibiotic combinations (azithromycin/ciprofloxacin, azithromycin/methylene blue, rifampin/ciprofloxacin, rifampin/methylene blue) completely eradicated the biofilm B. henselae after treatment for 6 days.

CONCLUSIONS

These findings may facilitate development of more effective treatment of persistent Bartonella infections in the future.

Ocular complications of cat scratch disease

Cat scratch disease (CSD) in humans is caused by infection with Bartonella henselae or other Bartonella spp. The name of the disease reflects the fact that patients frequently have a history of contact (often involving bites or scratches) with infected cats. Patients with CSD typically develop lesions at the site where the skin is broken together with regional lymphadenopathy but may go on to exhibit systemic symptoms and with deep-seated infections at a range of sites including the eye. Patients with CSD may present with a range of inflammatory eye conditions, including Parinaud's oculoglandular syndrome, neuroretinitis, multifocal retinitis, uveitis and retinal artery occlusion. Bartonella spp. are fastidious bacteria that are difficult to culture from clinical specimens so microbiological diagnosis is frequently made on the basis of positive serology for anti-Bartonella antibodies or detection of bacterial DNA by PCR. Due to the lack of clinical trials, the evidence base for optimal management of patients with CSD-associated eye infections (including the role of antibiotics) is weak, being derived from single reports or small, uncontrolled case series.

Cat-dependent diseases cost Australia AU$6 billion per year through impacts on human health and livestock production

Abstract ContextCats are the definitive or primary host for pathogens that cause diseases in people and livestock. These cat-dependent diseases would not occur in Australia if cats had not been introduced, and their ongoing persistence depends on contacts with cats. Toxoplasma gondii is a protozoan parasite that cycles between cats and any other warm-blooded animals. People infected by T. gondii may appear asymptomatic, or have a mild illness, or experience severe, potentially lethal symptoms; the parasite may also affect behaviour and mental health. T. gondii is also a major contributor to spontaneous abortion in sheep and goats. Two species of Sarcocystis, another genus of protozoan parasite, cycle through cats and sheep, causing macroscopic cysts to form in sheep tissues that reduce meat saleability. Toxocara cati, the cat roundworm, causes minor illnesses in humans and livestock, and the bacterium Bartonella henselae causes cat scratch disease, an infection that can be contracted by people when scratched or bitten by cats carrying the pathogen. AimsWe estimated the economic costs of cat-dependent pathogens in Australia. MethodsWe collated national and global data on infection rates, health and production consequences. Key resultsWe estimated the costs of two cat-dependent diseases (toxoplasmosis, cat scratch disease) in people at AU$6.06 billion (plausible range AU$2.11–10.7 billion) annually, and the costs to livestock production from toxoplasmosis and sarcocystosis at AU$11.7 million (plausible range AU$7.67–18.3 million). Most of the human health costs are due to the associations between T. gondii and higher rates of traffic accidents and mental illness in people. The causality behind these associations remains uncertain, so those costs may be overestimated. Conversely, our estimates are incomplete, infections and illness are under-reported or misdiagnosed, and our understanding of disease outcomes is still imperfect, all of which make our costs underestimated. ConclusionsOur analysis suggests that substantial benefits to public health and livestock production could be realised by reducing exposure to cats and breaking parasite transmission cycles. ImplicationsReducing feral cat populations in farming and urban areas, reducing the pet cat population and increasing rates of pet cat containment could help reduce the burden of cat-dependent diseases to people and livestock.

Update on Bartonella neuroretinitis

PURPOSE

To review the clinical features, diagnosis, treatment modalities, and prognosis of Bartonella-associated neuroretinitis.

METHODS

This is a narrative review on Bartonella-associated neuroretinitis including general and ophthalmological aspects of the disease. A comprehensive literature review between January 1950 and September 2018 was conducted in PubMed database. Epidemiology, clinical features, diagnosis, treatment, and prognosis of Bartonella neuroretinitis were reviewed.

RESULTS

Cat scratch disease (CSD) is a worldwide distributed systemic infectious disease caused by a bacterium, Bartonella henselae (B. henselae) which is usually transmitted to humans through contact with infected cats. Ocular manifestations of CSD are diverse, with neuroretinitis and superficial retinal infiltrates being the most common and typical manifestations. Neuroretinitis typically presents as optic disc edema with a partial or complete macular star in association with mild vitritis. Macular star may be absent at the initial presentation, becoming evident 1-2 weeks after the onset of optic disc edema. Diagnosis of CSD is confirmed by reliable laboratory tests. Neuroretinitis usually has a self-limited course. Antibiotic therapy is required for severe systemic disease and vision-threatening ocular involvement. The adjunctive use of oral corticosteroids may further improve the visual outcome.

CONCLUSIONS

The diagnosis of Bartonella-associated neuroretinitis is based on typical clinical findings and positive serology. The prognosis is usually favorable in immunocompetent individuals.

The seroprevalence of Bartonella spp. in the blood of patients with musculoskeletal complaints and blood donors, Poland: a pilot study

BACKGROUND

Bartonella spp. can cause a variety of diseases, such as lymphadenopathies, cat scratch disease, and trench fever, but can also give rise to many non-specific symptoms. No data exists regarding the prevalence of Bartonella spp. in patients with musculoskeletal complaints, nor among blood donors in Poland.

METHODS

The presence of anti-Bartonella IgM and IgG in the serum of blood donors (n = 65) (Lodz, Poland) and in the patients of the Department of Rheumatology Clinic (n = 40) suffering from musculoskeletal symptoms was tested by immunofluorescence. Blood samples were cultured on enriched media. Epidemiological questionnaires were used to identify key potential risk factors, such as sex, age, contact with companion animals, and bites from insects or animals.

RESULTS

Altogether, 27 of the 105 tested subjects were seropositive for Bartonella henselae IgG (23%) and three for Bartonella quintana IgG (2.85%); IgMs against B. henselae were found in three individuals (2.85%), and IgMs against B. quintana were found in one (1.54%). No statistically significant difference was found between the prevalence of B. henselae in the blood of donors or patients and the presence of unexplained musculoskeletal complaints (23% vs 30%). Individuals who had kept or been scratched by cats were not more likely to be B. henselae seropositive (p > 0.01). Tick bites were more commonly reported in patients, but insignificantly (p > 0.01).

CONCLUSION

This is the first report of a high seroprevalence of anti-Bartonella IgG in patients with musculoskeletal symptoms and in blood donors in Poland. The obtained results indicate that such seroprevalence may have a possible significance in the development of musculoskeletal symptoms, although it should be confirmed on a larger group of patients. Asymptomatic bacteremia might occur and pose a threat to recipients of blood from infected donors. Hence, there is a need for more detailed research, including molecular biology methods, to clarify the potential risk of Bartonella spp. being spread to immunocompromised individuals.

KEY POINTS

• This is the first study presenting high seroprevalence of Bartonella spp. in Poland. • IgG and IgM antibodies against B. quintana were found in blood samples of blood donors.

The trimeric autotransporter adhesin BadA is required for in vitro biofilm formation by Bartonella henselae

Bartonella henselae (Bh) is a Gram-negative rod transmitted to humans by a scratch from the common house cat. Infection of humans with Bh can result in a range of clinical diseases including lymphadenopathy observed in cat-scratch disease and more serious disease from persistent bacteremia. It is a common cause of blood-culture negative endocarditis as the bacterium is capable of growing as aggregates, and forming biofilms on infected native and prosthetic heart valves. The aggregative growth requires a trimeric autotransporter adhesin (TAA) called Bartonella adhesin A (BadA). TAAs are found in all Bartonella species and many other Gram-negative bacteria. Using Bh Houston-1, Bh Houston-1 ∆badA and Bh Houston-1 ∆badA/pNS2PTrc badA (a partial complement of badA coding for a truncated protein of 741 amino acid residues), we analyze the role of BadA in adhesion and biofilm formation. We also investigate the role of environmental factors such as temperature on badA expression and biofilm formation. Real-time cell adhesion monitoring and electron microscopy show that Bh Houston-1 adheres and forms biofilm more efficiently than the Bh Houston-1 ∆badA. Deletion of the badA gene significantly decreases adhesion, the first step in biofilm formation in vitro, which is partially restored in Bh Houston-1 ∆badA/pNS2PTrc badA. The biofilm formed by Bh Houston-1 includes polysaccharides, proteins, and DNA components and is susceptible to enzymatic degradation of these components. Furthermore, both pH and temperature influence both badA expression and biofilm formation. We conclude that BadA is required for optimal adhesion, agglutination and biofilm formation.

Ocular manifestations of bartonellosis

PURPOSE OF REVIEW

To review the systemic and ocular complications of Bartonella spp. infections specifically cat scratch disease, encompassing epidemiology, laboratory diagnostics, ophthalmic imagining, and treatment.

RECENT FINDINGS

Recent studies have shown that ocular manifestations occur in approximately 4.4% of cat scratch disease patients. The annual prevalence is lower than previously reported to be approximately 12 500 cases annually. Mainstay treatment continues to be oral antibiotics with and without corticosteroids and is dependent on associated systemic manifestations, age, and patient immune status. More recently anti-VEGF agents have been used for complications such as cystoid macular edema and choroidal neovascularization.

SUMMARY

Bartonella spp. infections continue to be a common cause uveitis with ophthalmic manifestations ranging from neuroretinits, vascular occlusions, to choroidal granulomas. Review of associated risk factors including contact with feline reservoirs will aid in recognition and diagnosis of this disease entity. Laboratory diagnostics continue to improve to help with the diagnosis of this entity.

Bartonella henselae infection presenting as cervical spine osteomyelitis: case report

Bartonella henselae is a gram-negative bacillus implicated in cat-scratch disease. Cat-scratch disease is usually self-limiting and results in local lymphadenopathy. In rare circumstances, patients may develop endocarditis, neuroretinitis, or osteomyelitis. Osteomyelitis of the cervical spine is exceedingly rare, especially in the pediatric population, and to date there have been only 4 previously reported cases of cervical spine osteomyelitis caused by B. henselae, all of which were treated surgically. In this article, the authors report the case of a 7-year-old boy who presented with neck swelling and was found to have a C2-4 paravertebral B. henselae abscess with osteomyelitis of C-3 and epidural extension. To the authors' knowledge, this represents the first case in the literature of a cervical spine B. henselae infection managed conservatively.

Cat-scratch disease: ocular manifestations and treatment outcome

PURPOSE

To characterize cat-scratch disease (CSD) ocular manifestations and visual outcome and evaluate the effect of systemic antibiotics and corticosteroids on final visual acuity (VA).

METHODS

Multicentre retrospective cohort study. Medical records of 86 patients with ocular disease (107 eyes) of 3222 patients identified in a national CSD surveillance study were reviewed.

RESULTS

Mean age was 35.1 ± 14.2 years. Median follow-up was 20 weeks (range 1-806 weeks). Of 94/107 (88%) eyes with swollen disc, 60 (64%) had neuroretinitis at presentation, 14 (15%) developed neuroretinitis during follow-up, and 20 (21%) were diagnosed with inflammatory disc oedema. Optic nerve head lesion, uveitis, optic neuropathy and retinal vessel occlusion were found in 43 (40%), 38 (36%), 34 (33%) and 8 (7%) eyes, respectively. Good VA (better than 20/40), moderate vision loss (20/40-20/200) and severe vision loss (worse than 20/200) were found in 26/79 (33%), 35/79 (44%) and 18/79 (23%) eyes at baseline and in 63/79 (80%), 11/79 (14%) and 5/79 (6%) eyes at final follow-up, respectively (p < 0.001). Significant VA improvement (defined as improvement of ≥3 Snellen lines at final follow-up compared to baseline) occurred in 12/24 (50%) eyes treated with antibiotics compared with 14/16 (88%) eyes treated with antibiotics and corticosteroids (p = 0.02). Multivariate logistic regression was suggestive of the same association (odds ratio 7.0; 95% CI 1.3-37.7; p = 0.024).

CONCLUSION

Optic nerve head lesion is a common and unique manifestation of ocular CSD. Most patients improved and had final good VA. Combined antibiotics and corticosteroid treatment was associated with a better visual outcome.

Lymphadenitis associated with cat-scratch disease simulating a neoplasm: Imaging findings with histopathological associations

The lymphadenitis associated with cat-scratch disease (CSD) is often confused with neoplasms by a number of radiologists and clinicians, and consequently, unnecessary invasive procedures or surgeries are performed. In the present study, the contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) findings of 10 patients (6 men and 4 women) with clinically and pathologically confirmed lymphadenitis associated with CSD were retrospectively analyzed (CT in 3 patients, MRI in 6 patients, and CT and MRI in 1 patient) at The Second Affiliated Hospital of Zhejiang University School of Medicine (Hangzhou, China) between January 2007 and November 2014. As a result, 17 enlarged lymph nodes were identified in 10 cases. The 5 nodes identified by CT scan exhibited relatively inhomogeneous isodensity to muscle, with patchy low density in the center. All 14 nodes identified by MRI scan exhibited homogeneous or heterogeneous isointensity to muscle or slightly increased intensity compared with that of muscle on T1-weighted images (T1WI), and homogeneous or heterogeneous hyperintensity on fat-suppressed T2WI. Following enhancement, all 17 enlarged lymph nodes associated with CSD demonstrated the following 3 different enhancement patterns: Moderate homogeneous enhancement (n=8), which was associated with histologically identified early disease stage; marked heterogeneous enhancement with no enhancement of the necrotic areas (n=4), and heterogeneous enhancement with progressively ‘spoke-wheel-like’ (defined as radiating enhancement from the center) enhancement of the patchy low-density area (n=1), which was associated with histologically identified intermediate disease stage; and astral low-density/hypointensity with marked enhancement (n=2) or a ‘rose flower’ sign (n=2), which was associated with histologically identified late disease stage. We hypothesized that the CT and MRI results of lymphadenitis in CSD may be associated with the pathological features. It may be suggested that the diagnosis of CSD may be formed when considering the characteristic CT and MRI features of astral low-density/hypointensity with marked enhancement or a ‘rose flower’ sign (defined as marginal petaloid enhancement) in the late disease stage, or the MRI results of homogeneous, moderate enhancement in the early disease stage, or the CT/MRI data of heterogeneous enhancement with non-enhancing area in the center in the intermediate disease stage, in solitary or multiple enlarged lymph nodes associated with general subcutaneous edema in the vicinity of the nodes on CT/MRI and with a history of cat exposure.

Granulomatous diseases of the breast and axilla: radiological findings with pathological correlation

Objectives

This article reviews our experience and describes the literature findings of granulomatous diseases of the breast and axilla.

Methods

After approval of the Institutional Review Board was obtained, the surgical pathological records from January 2000 to January 2017 were searched for the keyword granulomatous. Clinical, imaging and histology findings were reviewed by both a fellowship-trained radiologist and a breast-imaging consultant radiologist, reviewing 127 patients (age range, 32–86 years; 126 women and 1 man).

Results

Most common causes of granulomatous lesions of the breast and axilla included silicone granulomas 33% (n = 42), fat necrosis 29% (n = 37) and suture granulomas 11% (n = 14). In 16% (n = 20), no cause could be found and clinical history was consistent with idiopathic granulomatous mastitis. Other granulomatous aetiologies included granulomatous infections, sarcoidosis and Sjögren’s syndrome. Causes of axillary granulomatous disease were similar to the breast; however, a case of cat-scratch disease was found that only involved the axillary lymph nodes. They can have a variable appearance on imaging and may mimic malignancy with irregular masses seen on mammography, ultrasound and magnetic resonance imaging. Fistulas to the skin and nipple retraction can suggest chronicity and a granulomatous aetiology. Combination of clinical history, laboratory and imaging findings can be diagnostic.

Conclusions

Granulomatous processes of the breast are rare. The diagnosis can, however, be made if there is relevant history (prior trauma, silicone breast implants, lactation), laboratory (systemic or infectious processes) and imaging findings (fistula, nipple retraction). Recognising these entities is important for establishing pathological concordance after biopsy and for preventing unnecessary treatment.

Teaching points

Breast granulomatous are rare but can mimic breast carcinoma on imaging

Imaging with clinical and laboratory findings can correctly diagnosis specific granulomatous breast diseases

Recognition of the imaging findings allows appropriate pathological concordance and treatment

Cat-Scratch Disease in the United States, 2005-2013

Each year, this preventable disease affects about 12,500 persons, mostly those who live in the South and are 5–9 years of age.

Cat-scratch disease (CSD) is mostly preventable. More information about the epidemiology and extent of CSD would help direct prevention efforts to those at highest risk. To gain such information, we reviewed the 2005–2013 MarketScan national health insurance claims databases and identified patients <65 years of age with an inpatient admission or outpatient visit that included a CSD code from the International Classification of Diseases, Ninth Revision, Clinical Modification. Incidence of CSD was highest among those who lived in the southern United States (6.4 cases/100,000 population) and among children 5–9 years of age (9.4 cases/100,000 population). Inpatients were significantly more likely than outpatients to be male and 50–64 years of age. We estimate that each year, 12,000 outpatients are given a CSD diagnosis and 500 inpatients are hospitalized for CSD. Prevention measures (e.g., flea control for cats) are particularly helpful in southern states and in households with children.

Depressiveness and Neuroticism in Bartonella Seropositive and Seronegative Subjects-Preregistered Case-Controls Study

Several recent studies have demonstrated the association of cat-related injuries with major depression and with depressiveness in the general population. It was suggested that cat-scratch disease, the infection with the bacterium Bartonella henselae, can be responsible for the observed association. However, no direct evidence for the role of the Bartonella infection in this association has been published until now. In this preregistered case-controls study performed on 250 healthy subjects tested earlier for the presence of anti-Toxoplasma IgG antibodies, we searched for the positive association between presence of anamnestic anti-Bartonella IgG antibodies and depressiveness measured with Beck II inventory, depression subscale of neuroticism measured with N-70 questionnaire, and self-reported health problems. We found that that Bartonella seropositivity was positively correlated with Beck depression only in Toxoplasma-seronegative men and negatively correlated with health in Toxoplasma-seronegative women. Bartonella seropositivity expressed protective effects against Toxoplasma seropositivity-associated increased neuroticism in men while Toxoplasma-seropositivity expressed protective effects against Bartonella seropositivity-associated health problems in women. A comparison of the patterns of association of mental and physical health problems with Bartonella seropositivity and with reported cat-related injury suggests that different factor, possibly infection with different pathogen transmitted by cat related-injuries than the B. henselae, is responsible for the observed association of cat related-injuries with depressiveness and major depression. The existence of complex interactions between Bartonella seropositivity, Toxoplasma seropositivity, and sex also suggest that the effect of symbionts on the host's phenotype must by always studied in the context of other infections, and separately for men and women.

Utility of Bartonella henselae IgM Western Blot Bands for Serodiagnosis of Cat Scratch Disease

We evaluated the utility of Western blot (WB) bands of Bartonella henselae in detecting anti-B. henselae immunoglobulin M (IgM) for serodiagnosis of cat scratch disease (CSD). IgM band patterns were examined using sera from 92 patients clinically suspected of having CSD and from 130 healthy individuals. Positive WB bands were observed in 49 (53.5%) of the 92 patient sera. Three bands at 8 to 10, 31 to 35, and 70 kDa were regarded as relevant for B. henselae because all of the positive sera yielded at least one of the three bands, and none of the healthy control sera showed reactivity to any of them. In contrast, the positive rate of the patient sera by conventional indirect fluorescence antibody assay (IFA) for B. henselae IgM was 28.3% (26/92) among the patients. These finding suggest that the IgM-WB assay, although cumbersome to perform, can be used for confirmatory diagnosis of CSD with no false positivity in the control sera. Purification of proteins in the specific bands may contribute to the development of an IgM enzyme-linked immunosorbent assay (IgM-ELISA) with improved specificity and sensitivity.

Bartonella Species, an Emerging Cause of Blood-Culture-Negative Endocarditis

Since the reclassification of the genus Bartonella in 1993, the number of species has grown from 1 to 45 currently designated members. Likewise, the association of different Bartonella species with human disease continues to grow, as does the range of clinical presentations associated with these bacteria. Among these, blood-culture-negative endocarditis stands out as a common, often undiagnosed, clinical presentation of infection with several different Bartonella species. The limitations of laboratory tests resulting in this underdiagnosis of Bartonella endocarditis are discussed. The varied clinical picture of Bartonella infection and a review of clinical aspects of endocarditis caused by Bartonella are presented. We also summarize the current knowledge of the molecular basis of Bartonella pathogenesis, focusing on surface adhesins in the two Bartonella species that most commonly cause endocarditis, B. henselae and B. quintana. We discuss evidence that surface adhesins are important factors for autoaggregation and biofilm formation by Bartonella species. Finally, we propose that biofilm formation is a critical step in the formation of vegetative masses during Bartonella-mediated endocarditis and represents a potential reservoir for persistence by these bacteria.

Disseminated cat-scratch disease presenting as nausea, diarrhea, and weight loss without fever in a heart transplant recipient

We report the case of an afebrile 59-year-old heart transplant recipient presenting with nausea, vomiting, diarrhea, weight loss, and diffuse lymphadenopathy. Lymph node biopsies revealed non-caseating granulomatous inflammation. Cat-scratch disease was confirmed by serologic studies, Warthin-Starry staining, and polymerase chain reaction testing of lymph node tissue. The patient's symptoms resolved with 3 months of doxycycline. We review clinical presentations of Bartonella henselae infection and review diagnostic approaches for B. henselae in this patient population.

The seroprevalence of Bartonella henselae in healthy adults in Korea

BACKGROUND/AIMS

Cat-scratch disease (CSD), caused by Bartonella henselae is one of the most common zoonosis. However, only several cases of B. henselae infection have been reported in Korea. This study investigated the seroprevalence of B. henselae in healthy adults and related risk factors.

METHODS

Serum samples from 300 healthy participants were analyzed using an immunoglobulin G immunof luorescence assay (IFA) for B. henselae isolated in Korea. Surveys on the risk factors for B. henselae infection were conducted simultaneously.

RESULTS

Of the participants, 47.7% and 15.0% raised dogs and cats, respectively. The overall seroprevalence of B. henselae was 15.0% (IFA titer ≥ 1:64). Participants who had raised cats showed 22.2% seropositivity against B. henselae, and those with no experience with cats showed 13.7% seroprevalence (p = 0.17). Participants who had cats as pets or been scratched by cats, showed 9.8% seropositivity against B. henselae (IFA titer ≥ 1:256). However, those who had not raised or been scratched by a cat showed 2.0% seropositivity (p = 0.015).

CONCLUSIONS

In Korea, the seroprevalence of B. henselae is higher than expected, suggesting that Bartonella infection due to B. henselae is not uncommon. Cats are proposed to play a more important role than dogs in transmission of CSD.

MR imaging of adult acute infectious encephalitis

BACKGROUND

Imaging is a key tool for the diagnosis of acute encephalitis. Brain CT scan must be urgently performed to rule out a brain lesion with mass effect that would contraindicate lumbar puncture. Brain MRI is less accessible than CT scan, but can provide crucial information with patients presenting with acute encephalitis.

METHOD

We performed a literature review on PubMed on April 1, 2015 with the search terms "MRI" and "encephalitis".

RESULTS

We first described the various brain MRI abnormalities associated with each pathogen of acute encephalitis (HSV, VZV, other viral agents targeting immunocompromised patients or travelers; tuberculosis, listeriosis, other less frequent bacterial agents). Then, we identified specific patterns of brain MRI abnomalies that may suggest a particular pathogen. Limbic encephalitis is highly suggestive of HSV; it also occurs less frequently in encephalitis due to HHV6, syphillis, Whipple's disease and HIV primary infection. Rhombencephalitis is suggestive of tuberculosis and listeriosis. Acute ischemic lesions can occur in patients presenting with severe bacterial encephalitis, tuberculosis, VZV encephalitis, syphilis, and fungal infections.

CONCLUSION

Brain MRI plays a crucial role in the diagnosis of acute encephalitis. It detects brain signal changes that reinforce the clinical suspicion of encephalitis, especially when the causative agent is not identified by lumbar puncture; it can suggest a particular pathogen based on the pattern of brain abnormalities and it rules out important differential diagnosis (vascular, tumoral or inflammatory causes).

Epitrochlear cat scratch disease: unique imaging features allowing differentiation from other soft tissue masses of the medial arm

OBJECTIVE

Evaluate anatomic and imaging features of epitrochlear regional adenopathy secondary to cat scratch disease (CSD) to assist differentiation of CSD from other soft tissue masses at the elbow.

MATERIALS AND METHODS

Retrospective review of 24 confirmed cases of CSD. Patient demographics, clinical presentation and radiographic (R; n = 10), CT (n = 3), ultrasound (US; n = 5), and MR (n = 21) images were reviewed. Lesion location, size, number of masses, and intrinsic characteristics on R/CT/US/MR and presence of soft tissue inflammatory changes or adjacent bone or joint involvement were established through the consensus interpretation by four musculoskeletal radiologists.

RESULTS

The average patient age was 18.6 years. Mass location was anterior and superficial to the medial intermuscular septum (100 %) with the masses posterior or posteromedial to the basilic vein (92 %). Three or fewer lymph nodes were involved in 92 %. Masses were noncalcified with adjacent inflammatory change (R = 90 %, CT = 100 %). US showed hypoechoic soft tissue echogenicity masses with defined to minimally irregular margins (80 %) and preserved central hilar hypervascularity on Doppler (100 % of cases). On MR, masses were T1 isointense (62 %), T2 isointense (54 %), intermediate signal on T2 images with fat suppression (55 %), and had perilesional inflammatory changes (95 %), perilesional fluid collections (38 %), adjacent muscle edema (81 %), hyperintense cental hilar vascular enhancement (65 %) and occasional preserved central hilar fat (14 %).

CONCLUSION

Cat scratch disease is suggested by the characteristic location of a medial epitrochlear mass superficial to the brachial fascia and posterior to the basilic vein with surrounding inflammatory changes and preservation of hilar vascular architecture, hilar enhancement and occasional hilar fat.

Cat-scratch disease: Otolaryngologic manifestations and management

OBJECTIVE:

The bacteria Bartonella henselae has been known as the principal causative agent of cat-scratch disease (CSD) since 1992. It is an important cause of infectious lymphadenopathies in the head and neck. Nevertheless, CSD often remains unrecognized in cases of cervicofacial lymph node enlargement.

STUDY DESIGN:

Between January 1997 and May 2003, we conducted a prospective clinical study including 721 patients with primarily unclear masses in the head and neck.

RESULTS:

CSD was diagnosed by serology and molecular investigations in 99 patients (13.7%; median age 33 years). Cervicofacial lymphadenopathy was the most common manifestation. Atypical manifestation of CSD including Parinaud's oculoglandular syndrome, swelling of the parotid gland and erythema nodosum were diagnosed in 8.1%, 8.1%, and 2.0% of cases, respectively.

CONCLUSIONS:

Our results demonstrate that CSD is a major cause of enlarged cervicofacial lymph nodes and should therefore be included in the differential diagnosis of lymphadenopathy in the head and neck region.

Risk Factors for Bartonella species Infection in Blood Donors from Southeast Brazil

Bacteria from the genus Bartonella are emerging blood-borne bacteria, capable of causing long-lasting infection in marine and terrestrial mammals, including humans. Bartonella are generally well adapted to their main host, causing persistent infection without clinical manifestation. However, these organisms may cause severe disease in natural or accidental hosts. In humans, Bartonella species have been detected from sick patients presented with diverse disease manifestations, including cat scratch disease, trench fever, bacillary angiomatosis, endocarditis, polyarthritis, or granulomatous inflammatory disease. However, with the advances in diagnostic methods, subclinical bloodstream infection in humans has been reported, with the potential for transmission through blood transfusion been recently investigated by our group. The objective of this study was to determine the risk factors associated with Bartonella species infection in asymptomatic blood donors presented at a major blood bank in Southeastern Brazil. Five hundred blood donors were randomly enrolled and tested for Bartonella species infection by specialized blood cultured coupled with high-sensitive PCR assays. Epidemiological questionnaires were designed to cover major potential risk factors, such as age, gender, ethnicity, contact with companion animals, livestock, or wild animals, bites from insects or animal, economical status, among other factors. Based on multivariate logistic regression, bloodstream infection with B. henselae or B. clarridgeiae was associated with cat contact (adjusted OR: 3.4, 95% CI: 1.1–9.6) or history of tick bite (adjusted OR: 3.7, 95% CI: 1.3–13.4). These risk factors should be considered during donor screening, as bacteremia by these Bartonella species may not be detected by traditional laboratory screening methods, and it may be transmitted by blood transfusion.

Bacteria from the genus Bartonella are capable of causing long-lasting infection. Despite the fact that these bacteria may cause several diseases such as cat scratch disease, trench fever, and infection of cardiac valves, which can be fatal, they may also cause asymptomatic infection in humans. Several blood-sucking arthropods have been suggested or confirmed as responsible for transmitting these bacteria, including sandflies, body lice, fleas, ticks, and keds. In this study, 500 asymptomatic human blood donors from Brazil were screened for infection with species of Bartonella by blood culture coupled with molecular detection and genetic sequencing, and risk factors associated with such infection were identified. In this population, contact with cats and history of tick bite were significantly associated with human infection by Bartonella species. Since laboratory screening of donated blood for the presence of Bartonella species is not generally performed by blood banks, these risk factors should be should be considered during donor screening in order to avoid transmission of Bartonella species by blood transfusion.

Cat scratches, not bites, are associated with unipolar depression--cross-sectional study

BACKGROUND

A recent study performed on 1.3 million patients showed a strong association between being bitten by a cat and probability of being diagnosed with depression. Authors suggested that infection with cat parasite Toxoplasma could be the reason for this association.

METHOD

A cross sectional internet study on a non-clinical population of 5,535 subjects was undertaken.

RESULTS

The subjects that reported having been bitten by a dog and a cat or scratched by a cat have higher Beck depression score. They were more likely to have visited psychiatrists, psychotherapists and neurologists in past two years, to have been previously diagnosed with depression (but not with bipolar disorder). Multivariate analysis of models with cat biting, cat scratching, toxoplasmosis, the number of cats at home, and the age of subjects as independent variables showed that only cat scratching had positive effect on depression (p = 0.004). Cat biting and toxoplasmosis had no effect on the depression, and the number of cats at home had a negative effect on depression (p = 0.021).

CONCLUSIONS

Absence of association between toxoplasmosis and depression and five times stronger association of depression with cat scratching than with cat biting suggests that the pathogen responsible for mood disorders in animals-injured subjects is probably not the protozoon Toxoplasma gondii but another organism; possibly the agent of cat-scratched disease - the bacteria Bartonella henselae.