A case report of diagnosis of cat-scratch disease using metagenomic next-generation sequencing

Cat-scratch disease (CSD) is an anthropozoonotic infection caused by Bartonella henselae, and it is one of the most common causes of lymph node infections in children and adolescents. B. henselae, belonging to the genus Bartonella, is a common human pathogen of human beings. CSD commonly develops as a result of cat scratches and bites or when injured skin comes into contact with cat saliva. The manifestation of CSD clinically differs for each patient based on their immune system. Individuals who have healthy immune systems generally manifest minimal clinical symptoms and do not necessitate any form of treatment. However, patients who have hypo-immunity require prompt medical attention due to the potential manifestation of severe symptoms that affect multiple systems of the body. Long latency and atypical clinical manifestations are characteristics of CSD. Bartonella isolation and identification are challenging procedures that require specialized equipment. There is no gold standard method for CSD diagnosis, and misdiagnosis and missed diagnosis rates are typically high. We present the case of a middle-aged male patient who developed fever, chills, anal distension, dizziness, and muscle pain for 10 days. The patient had a documented history of cat bites 1 month prior to the onset of symptoms. Following admission, he underwent an examination to determine superficial lymphadenopathy and hypoimmunity. Additionally, he had a fever during the disease. As the patient refused a needle biopsy of lymph nodes, metagenomic next-generation sequencing (mNGS) was employed and B. henselae was detected in the peripheral blood. The patient was diagnosed with CSD and treated with a combination of azithromycin and doxycycline. The fever symptoms were alleviated, and the patient was ultimately discharged. As a result of this case, we suggest that mNGS be used as a crucial supplementary diagnostic tool for individuals with compromised immune systems who may have CSD, especially when conventional diagnostic methods are inconclusive.

Metagenomic next-generation sequencing may assist diagnosis of cat-scratch disease

Bartonella henselae, the pathogen that causes cat-scratch disease (CSD), is relatively rare in the clinic. CSD usually causes mild clinical manifestations, which self-heal in a matter of weeks. However, in immunocompromised patients, CSD may cause systemic disorders that can lead to critical illness. Due to the diversity of symptom signs and the lack of a golden standard for diagnosis, identifying atypical CSD in a timely manner presents a challenge. Metagenomic next-generation sequencing (mNGS), is a promising technology that has been widely used in the detection of pathogens in clinical infectious diseases in recent years. mNGS can detect multiple pathogens quickly and accurately from any given source. Here, we present a case of atypical CSD, which was diagnosed using mNGS. The patient manifested a fever of unknown infectious origin, and routine antibiotic treatment was ineffective. mNGS was employed to test the patient’s peripheral blood, which led to the detection of B. henselae. This was rarely seen in previous CSD reports. We surmised that the patient presented with atypical CSD and thus a targeted therapy was recommended. Crucially, the patient recovered rapidly. Based on this case study findings, we recommend that CSD should be included in the differential diagnosis for fever of unknown origin and that mNGS may be helpful in the diagnosis of CSD.

Posterior Segment Manifestations of Cat-scratch Disease: A Mini-review of the Clinical and Multi-modal Imaging Features

Bartonella henselae, an intracellular gram-negative bacillus, is usually transmitted from infected cats to humans by direct or indirect contact. The bacterium mainly infects erythrocytes and endothelial cells thereby leading to so called cat-scratch disease (CSD) and may present with various localised and/or systemic manifestations. The eye is the most commonly affected organ in disseminated CSD and ocular bartonellosis has been reported in 5-10% of CSD patients. The most well-known clinical feature of ocular bartonellosis is neuroretinitis but various sight-threatening posterior segment lesions involving the optic nerve, retinal vasculature, retinal and choroidal tissues may occur during the disease course. This mini-review aims to overview both the clinical and multi-modal imaging characteristics of posterior ocular segment manifestations of CSD.

As a Failure to Follow Basic Medical Rules for a Sample, Has a Costly Diagnosis of a Zoonosis

Cat-scratch disease can be transmitted from cats and dogs in winter. It is usually self-limited and caused by Bartonella henselae. It may cause serious symptoms, including neurological findings, especially in immune-deficient patients. A female patient was referred to our outpatient clinic at the age of 3 years and 10 months with a preliminary diagnosis of neurodegenerative metabolic disease. Her complaints began after a stray cat scratched her. We found out that the hospital to which she was admitted provided only local wound care due to her history of contact with a cat and that she was vaccinated against rabies. Her body temperature increased, her neck lymph nodes became swollen, and she developed otitis and mastoiditis after 1 month. Additionally, we discovered that she had deteriorated in her walking ability after 6 weeks and developed hand tremors after 10 weeks. It was discovered that previous centers to which the patient applied did not question cat contact. All metabolic tests performed for the differential diagnosis of last admission findings were considered nonspecific. Considering cat-scratch disease due to her clinical history, she was referred to the pediatric infection unit for a Bartonella henselae test, and the test result was 1/256 positive. Failure to follow basic medical rules might be costly in diagnosis and treatment. Cat scratch disease is a zoonosis and a major public health problem. In differential diagnosis, these medical procedures should always be considered before rare metabolic diseases.

Atypical bartonellosis in children: What do we know?

AIM

To characterise Bartonella infections in a paediatric population requiring hospital admission and review its treatment.

METHODS

Longitudinal observational retrospective data analysis of children and adolescents admitted with Bartonella infection at a paediatric tertiary hospital from 2010 to 2019.

RESULTS

We identified 16 cases of bartonellosis, with a mean age of 8.0 ± 4.5 years old, no sex predominance and 14 had contact with cats. Most of the cases occurred in fall and winter. Clinical presentations included osteomyelitis/arthritis (n = 9), hepatosplenic disease (n = 2), lymphadenitis (n = 2), neuroretinitis (n = 2) and encephalitis (n = 1). Clinical diagnosis was confirmed by serology (n = 16) and Bartonella DNA detection in patient's lymph nodes/hepatic lesion (n = 3). Therapeutic approach varied according to the clinical presentation: azithromycin in lymphadenitis, rifampicin plus ciprofloxacin in hepatosplenic disease, rifampicin and doxycycline in neuroretinitis, ceftriaxone in encephalitis and azithromycin, cotrimoxazole or rifampicin plus azithromycin, cefuroxime, ciprofloxacin or doxycycline in osteomyelitis/arthritis. Immunodeficiency was excluded in seven patients. Seven patients' cats were screened by veterinarians and treated when infected (n = 5).

CONCLUSIONS

In these clinical presentations, where other infections may be involved, a high index of suspicion is necessary, with emphasis on the epidemiological context. The association of systemic forms with immunodeficiency did not occur in our study. The lack of recommendations for treatment of atypical infection makes the approach of these cases a challenge. Randomised control studies are essential to define the best approach in each case.

A Case of Atypical Bartonellosis in a 4-Year-Old Immunocompetent Child

In most cases, infection due to Bartonella henselae causes a mild disease presenting with a regional lymphadenopathy frequently associated with a low-grade fever, headache, poor appetite and exhaustion that spontaneously resolves itself in a few weeks. As the infection is generally transmitted by cats through scratching or biting, the disease is named cat scratch disease (CSD). However, in 5–20% of cases, mainly in immunocompromised patients, systemic involvement can occur and CSD may result in major illness. This report describes a case of systemic CSD diagnosed in an immunocompetent 4-year-old child that can be used as an example of the problems that pediatricians must solve to reach a diagnosis of atypical CSD. Despite the child’s lack of history suggesting any contact with cats and the absence of regional lymphadenopathy, the presence of a high fever, deterioration of their general condition, increased inflammatory biomarkers, hepatosplenic lesions (i.e., multiple abscesses), pericardial effusion with mild mitral valve regurgitation and a mild dilatation of the proximal and medial portion of the right coronary artery, seroconversion for B. henselae (IgG 1:256) supported the diagnosis of atypical CSD. Administration of oral azithromycin was initiated (10 mg/kg/die for 3 days) with a progressive normalization of clinical, laboratory and US hepatosplenic and cardiac findings. This case shows that the diagnosis of atypical CSD is challenging. The nonspecific, composite and variable clinical features of this disease require a careful evaluation in order to achieve a precise diagnosis and to avoid both a delayed diagnosis and therapy with a risk of negative evolution.

Bartonella henselae IgM seropositivity in both adult and pediatric patients with diverse clinical conditions in Turkey

Bartonella henselae is the causative agent of cat scratch disease (CSD). In this study, we aimed to investigate the clinical data of patients with suspicion of CSD and delineate current epidemiological features.A total of 785 patients with suspected CSD were included in the study. B. henselae IgM antibody was determined by indirect fluorescent antibody (IFA) test using a commercial kit (Euroimmun, Germany). Sex, age, clinical pre-diagnosis and animal contact information of the patients were obtained from hospital electronic database records.Seventy-eight (9.9%) of 785 samples were seropositive. Out of 78 patients, 46 with animal contact data were further analyzed. Of these patients, 56% were male, and 41% were under 18 years of age. Seropositivity was more commonly observed in fall and winter. The most common finding was lymphadenitis (63%). Thirty-five patients (76%) had a previous history of animal contact (cat/dog). Of the 46 seropositive patients, 78.3, 15.2, 4.4, and 2.1% had titers of 1:80, 1:160, 1:320, and 1:640, respectively.Our study confirms that CSD is not rare in Turkey. Thus, it should always be considered in the differential diagnosis of patients presenting with lymphadenopathy in all age groups, particularly children. Questioning of cat exposure should never be neglected, especially in areas with intense population of stray cats, such as Istanbul.

Hemorrhage and Rupture of an Unusual Benign Liver Lesion in Pregnancy: A Case Report

Liver rupture in pregnancy is an acute condition with significant risk to the mother and fetus. It is known to occur with tumors such as hepatic adenoma, infective causes such as abscess, granulomatous diseases, and parasitic infections, and rarely spontaneously. Most of these conditions have overlapping clinicoradiological findings, almost always requiring histopathological confirmation. We report a case of a ruptured hepatic lesion, with an unusual diagnosis of Bartonella henselae infection causing cat-scratch disease, in a 24-year-old pregnant lady.

Felis Punctatis: Cat Claw-induced Punctures

Animal-induced conditions in humans predominantly present as infectious zoonoses. However, trauma-associated injuries from the teeth or claws can also occur. Several zoonotic infections can be transmitted by cats, a common household pet, to their owners. The clinical features of a woman who developed multiple sites of trauma-induced cutaneous punctures from her cat’s paws while it was kneading on her clothes-covered abdomen are described. The repetitive insertion and withdrawal of the sharp tips of the cat’s claws created distinctive groups of erythematous punctures on the patient’s skin. We suggest that Latin nomenclature be used to designate the name for this claw-induced dermatosis that includes not only the causative animal (felis for cat) but also a descriptive term for the skin lesions (punctatis for punctures): felis punctatis.

Bartonellosis in Chronic Kidney Disease: An Unrecognized and Unsuspected Diagnosis

Systemic cat scratch disease or bartonellosis is a clinical entity caused by Bartonella henselae, which manifests with necrotizing granulomas in visceral organs. The cat flea, Ctenocephalides felis, is the vector responsible for horizontal transmission of the disease from cat to cat, and its bite can also infect humans. In immunocompromised patients including chronic kidney disease and renal transplant recipients, it can cause persistent and disseminated cat scratch disease. The aim of this paper is to perform a systematic review of the studies that have addressed the diagnostic methods of cat scratch disease in chronic kidney disease and renal transplant recipients. This review was searched via electronic PubMed and Google scholar databases. Few qualitative full-text original articles in chronic kidney disease and kidney transplant were extracted. At this paper, 19 articles identified including six articles in chronic kidney disease and 13 articles in renal transplant recipients. Of these six identified case reports in chronic kidney disease, serology via immunofluorescence antibody test was led to diagnosis of cat scratch disease in five patients and a one patient showed nonreactive serologic test. Polymerase chain reaction usage to detect deoxyribonucleic acid in tissue biopsy and bone marrow biopsy was led to diagnosis. Cat scratch disease diagnosis in 13 renal transplant recipients was attained more by combining serology and polymerase chain reaction to detect deoxyribonucleic acid in tissue specimens. These selected studies demonstrate that serology and polymerase chain reaction via deoxyribonucleic acid extraction of tissue specimens yield the best outcome in diagnostic field of bartonellosis.

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.