Scalp eschar and neck lymph adenopathy after a tick bite (SENLAT) in Tuscany, Italy (2015-2022)

INTRODUCTION

The Scalp Eschar and Neck Lymph Adenopathy After a Tick Bite (SENLAT) syndrome is frequently caused by Rickettsia slovaca and Rickettsia raoultii. Only six microbiologically confirmed SENLAT cases have been reported in Italy between 1996 and 2021. We report ten cases of SENLAT seen between 2015 and 2022 in a tertiary care center in Tuscany, Italy.

CASES PRESENTATION

All patients were women; most common symptoms were scalp eschar on the site of tick bite (100%) and cervical lymphadenopathy (90%). No microbiological identification was obtained. Persistent alopecia, for several months to years, was observed in four patients. The known difficulty of microbiological diagnosis in SENLAT was worsened, in our cases, by factors as the absence of ticks available for identification and microbiological study, and antibiotic treatment administration previous to microbiological tests.

CONCLUSION

The report highlights the presence of SENLAT in Italy, aiming to raise the awareness toward the emergence of this clinical entity.

Morphologic Spectrum of Lymphadenopathy in Adult-onset Immunodeficiency (Anti-interferon-γ Autoantibodies)

Adult-onset immunodeficiency syndrome (AOIS) caused by anti-interferon-γ autoantibodies is an emerging disease. Affected patients present typically with systemic lymphadenopathy, fatigue, and fever. We studied 36 biopsy specimens, 31 lymph nodes, and 5 extranodal sites, of AOIS confirmed by serum autoantibody or QuantiFERON-TB Gold In-Tube assay. We describe the morphologic features and the results of ancillary studies, including special stains, immunohistochemistry, and molecular testing. The overall median age of these patients was 60.5 years (range, 41 to 83 y) with a male-to-female ratio of 20:16. All biopsy specimens showed nontuberculous mycobacterial infection, and most cases showed the following histologic features: capsular thickening with intranodal sclerosing fibrosis, irregularly distributed ill-formed granulomas or histiocytic aggregates with neutrophilic infiltration, interfollicular expansion by a polymorphic infiltrate with some Hodgkin-like cells that commonly effaces most of the nodal architecture and proliferation of high endothelial venules. In situ hybridization analysis for Epstein-Barr virus-encoded RNA showed scattered (<1%) to relatively more common (4% to 5%) positive cells in 29 of 30 (97%) tested specimens, reflecting immune dysregulation due to an interferon-γ defect. In the 31 lymph node specimens, 23 (74%) cases showed increased immunoglobulin G4-positive plasma cells (4 to 145/HPF; mean, 49.7/HPF) with focal areas of sclerosis reminiscent of immunoglobulin G4-related lymphadenopathy, 4 (13%) cases resembled, in part, nodular sclerosis Hodgkin lymphoma, and 9 (29%) cases mimicked T-cell lymphoma. Among 33 patients with available clinical follow-up, 20 (61%) showed persistent or refractory disease despite antimycobacterial therapy, and 1 patient died of the disease. We conclude that the presence of ill-defined granulomas, clusters of neutrophils adjacent to the histiocytic aggregates, and some Epstein-Barr virus-positive cells are features highly suggestive of AOIS. A high index of clinical suspicion and awareness of the morphologic features and differential diagnosis of AOIS are helpful for establishing the diagnosis.

Scratching Past Lymphadenopathy: A Case of Bartonella henselae Encephalitis

A previously healthy 6-year-old boy presented with new onset seizure activity and altered mental status. His prehospital course included prolonged fever, vague abdominal complaints, and unusual behavior. Neurological testing was unrevealing, and his symptoms slowly improved without intervention. His primary pediatrician had ordered serum antibody titers to Bartonella henselae for testing of prolonged fever in the setting of exposure to a kitten; these were found to be positive for both immunoglobulin G and immunoglobulin M. Further examination for organ involvement revealed splenic and liver micro-abscesses. After completion of his antibiotic course, the patient returned to his cognitive and neurologic baseline with resolution of his abdominal abscesses. This case emphasizes the importance of obtaining a thorough exposure history when evaluating for infectious causes of encephalitis. [Pediatr Ann. 2020;49(8):e359-e362.].

Etiological Evaluation of Patients with Lymphadenopathy by Clinical, Histopathological and Microbiological Assessment

Lymph node enlargement is a common presenting complaint in outpatient and inpatient department. The present observational cross sectional study was conducted in department of Internal Medicine, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh during the period from December 2014 to May 2016 to evaluate etiologies of significant lymphadenopathy by clinical, histopathological and microbiological assessment. Biopsy/FNA materials of 177 patients of 18-75 years age range with significant lymphadenopathy were sent for histopathology/cytology, Gram stain & culture, AFB stain & culture and Gene Xpert. Among them, 102(57.62%) were granulomatous lymphadenitis, 52(29.38%) were lymphoma, 12(6.78%) reactive lymphadenitis, 7(3.95%) metastatic malignancy, 2(1.13%) atypical lymphoid hyperplasia, 1(0.57%) myeloid sarcoma and 1(0.57%) chronic sialadenitis. Growth of MTB was on 23(22.55%) cases; among 102 granulomatous lymphadenitis and Gene Xpert was positive in 73(71.56%) cases with 100% Rif. sensitive. Gene Xpert is an important tool for diagnosis of tuberculous lymphadenitis. Time of symptoms to diagnosis of most of the TBL patients was within 2-8 months.

Cellulitis of the face associated with SENLAT caused by Rickettsia slovaca detected by qPCR on scalp eschar swab sample: An unusual case report and review of literature

BACKGROUND

Tick-borne rickettsioses are infectious diseases caused by obligate intracellular Gram-negative bacteria belonging to the spotted fever groupof Rickettsia.

METHODS

We describe an unusual case of SENLAT (Scalp eschar and neck lymphadenopathy after tick bite), caused byRickettsia slovaca, associated with a cellulitis of the face in a 70-year-old woman, and diagnosed using qPCR on a scalp eschar swab. We review the literature regarding cases of SENLAT-associated-cellulitis and case of SENLAT diagnosed by qPCR on scalp eschar swabs.

RESULTS

We found only one previous report of SENLAT associated with a cellulitis of the face. It was a nine-year-old French girl diagnosed by seroconversion for Rickettsia sp. Our review of the literature showed that qPCR on eschar swab samples is a less invasive method than performing cutaneous biopsy of the eschar and has good sensitivity and specificity (90% and 100%, respectively).

CONCLUSIONS

We report the second case of cellulitis of the face associated with the SENLAT syndrome. Detection of Rickettsia by qPCR on swab sample of the scalp eschar is a simple, noninvasive technique allowing rapid diagnosis and treatment when SENLAT is suspected.

[A chancre instead of cancer]

BACKGROUND

Syphilis (lues) is a sexually transmitted infection caused by the spirochete Treponema pallidum. In adolescents, the diagnosis of primary syphilis can be made promptly by taking a sexual medical history and inspecting the glans penis.

CASE DESCRIPTION

A 17-year-old male was referred to the paediatric oncology centre for additional diagnostics due to inguinal lymphadenopathy, with a strong suspicion of a malignant lymphoma. None of the physicians took a sexual medical history or investigated the glans penis, as a result of which essential information was lacking. The combination of inguinal lymphadenopathy and the ultrasound findings for the inguinal region made the physicians only consider a malignancy. However, it actually concerned a reactive lymphadenopathy associated with primary syphilis.

CONCLUSION

This case demonstrates that a full medical history and thorough physical examination can prevent the need for costly and invasive diagnostics.

Mycobacterium marinum lymphocutaneous infection

Mycobacterium marinum is a nontuberculous mycobacteria with worldwide distribution that lives in fresh or salt water and is responsible for infections in fish, and sometimes in humans. Human disease consists mainly of cutaneous nodules, but deep structure involvement may also occur. Diagnosis of M. marinum infection remains a challenge, with a considerable time delay between onset of symptoms and diagnosis. We present a 33-year-old man with no immunosuppressive history who was seen in our department with skin nodules over his hand and forearm, distributed in a sporotrichoid pattern. His hobbies included maintaining an aquarium of tropical fish. Histological examination of the patient's skin biopsy was compatible with the diagnosis of mycobacterial infection, and the Ziehl-Neelsen staining revealed acid-fast bacilli. Molecular techniques confirmed the suspicion of M. marinum infection. A necropsy was performed on one of the patient's fish, more specifically, a Poecilia reticulata, and resulted in identification of M. marinum from its gut. The patient was treated with clarithromycin, ethambutol, and rifampicin for 9 months, with clearance of infection.

Non-tubercular caseous adenopathy in Senegal

The authors report the case of a 22-year-old man referred seven months after the onset of papulo-nodular skin lesions, lymphadenopathy, splenomegaly and hepatomegaly. Mycologic and histologic examination of skin lesions enabled the diagnosis of African histoplasmosis, by Histoplasma capsulatum var duboisii. The lymph nodes were caseous. The culture in Lowenstein-Jensen medium was negative.

Isolated Mediastinal Lymphadenopathy Caused by Rhodococcus equi Infection

Mediastinal lymphadenopathy is common finding in thoracic surgery, and it often requires morphologic confirmation to establish the definitive diagnosis. The most frequent diagnoses are metastatic lung cancer, sarcoidosis, lymphoma, tuberculosis, and other causes of granulomatous infections. Rhodococcus equi is a rare pathogen in humans that mostly affects immunocompromised patients. This report presents a case with isolated mediastinal lymphadenopathy caused by Rhodococcus equi infection in a 71-year-old immunocompetent patient.

Leprosy manifesting with type 2 leprae reaction in a patient presenting with chronic fever: A case report

Leprosy is a chronic granulomatous disease involving the skin and nerves, leading to a debilitating condition. Leprosy has been controlled in most parts of the world; therefore physicians are not very well versed in the recognition, management and assessment of this disease. The protean manifestations of leprosy often lead to delays in diagnosis and increase the morbidity. We present a case of a 33-year-old male with fever, lymphadenopathy, nodular skin lesions, uveitis and arthritis. Lymphnode, bonemarrow and skin biopsy revealed 3+ AFB smear with negative AFB cultures, leading to the diagnosis of leprosy. The course of illness was complicated by flare of Erythema Nodosum Leprosum (ENL).

Characterization of the rhesus macaque (Macaca mulatta) scrub typhus model: Susceptibility to intradermal challenge with the human pathogen Orientia tsutsugamushi Karp

BACKGROUND

Scrub typhus is an important endemic disease in tropical Asia caused by Orientia tsutsugamushi for which no effective broadly protective vaccine is available. The successful evaluation of vaccine candidates requires well-characterized animal models and a better understanding of the immune response against O. tsutsugamushi. While many animal species have been used to study host immunity and vaccine responses in scrub typhus, only limited data exists in non-human primate (NHP) models.

METHODOLOGY/PRINCIPLE FINDINGS

In this study we evaluated a NHP scrub typhus disease model based on intradermal inoculation of O. tsutsugamushi Karp strain in rhesus macaques (n = 7). After an intradermal inoculation with 106 murine LD50 of O. tsutsugamushi at the anterior thigh (n = 4) or mock inoculum (n = 3), a series of time course investigations involving hematological, biochemical, molecular and immunological assays were performed, until day 28, when tissues were collected for pathology and immunohistochemistry. In all NHPs with O. tsutsugamushi inoculation, but not with mock inoculation, the development of a classic eschar with central necrosis, regional lymphadenopathy, and elevation of body temperature was observed on days 7-21 post inoculation (pi); bacteremia was detected by qPCR on days 6-18 pi; and alteration of liver enzyme function and increase of white blood cells on day 14 pi. Immune assays demonstrated raised serum levels of soluble cell adhesion molecules, anti-O. tsutsugamushi-specific antibody responses (IgM and IgG) and pathogen-specific cell-mediated immune responses in inoculated macaques. The qPCR assays detected O. tsutsugamushi in eschar, spleen, draining and non-draining lymph nodes, and immuno-double staining demonstrated intracellular O. tsutsugamushi in antigen presenting cells of eschars and lymph nodes.

CONCLUSIONS/SIGNIFICANCE

These data show the potential of using rhesus macaques as a scrub typhus model, for evaluation of correlates of protection in both natural and vaccine induced immunity, and support the evaluation of future vaccine candidates against scrub typhus.

Anti-interferon-γ autoantibody-associated disseminated Mycobacterium abscessus infection mimicking parotid cancer with multiple metastases: A case report

RATIONALE

Among the nontuberculous mycobacteria, Mycobacterium abscessus is a common cause of skin, soft tissue, and bone infections. However, disseminated M. abscessus infection that mimics cancer metastasis with an underlying relatively immunocompetent condition has rarely been reported.

PATIENT CONCERNS

A nonsmoking 73-year-old man with an underlying relatively immunocompetent condition reported a 2-month history of a mass in the region of his right parotid gland that had been steadily increasing in size.

DIAGNOSES

The head and neck computed tomography showed an avidly enhancing tumor with central necrosis in the right parotid region and lymphadenopathy bilaterally at neck levels II-V (<6 cm) with a necrotic core. The radiologist and otolaryngologist both suspected a diagnosis of right parotid gland cancer with metastasis.

INTERVENTIONS

The necrotic tissue was removed surgically, and Mycobacterium culture showed M. abscessus. We collected a blood sample and detected anti-interferon-γ autoantibody.

OUTCOMES

After 6 months of anti-M. abscessus treatment, physical examination showed remission of the parotid tumor, and axillary and supraclavicular lymphadenopathy.

LESSONS

We report a case of disseminated M. abscessus infection, which involved parotid glands with multiple lymphadenopathies in a person with an underlying relatively immunocompetent condition. Possible underlying mechanisms such as anti-interferon-γ autoantibody-associated immunodeficiency should be considered in a patient with disseminated M. abscessus infection without a known immunocompromised condition.

Staphylococcus lugdunensis cutaneous infection with sporotrichoid distribution

We report the occurrence of Staphylococcus lugdunensis cutaneous infection with sporotrichoid distribution of the left lower limb of a 60-year-old man. Recent studies have confirmed that Staphylococcus lugdunensis is a significant pathogen in causing skin and soft tissue infections that usually manifest in abscesses, surgical wound infections, and cellulitis. It used to be considered a skin commensal bacteria, but if unrecognized it can lead to  fulminant endocarditis, meningitis, skin abscesses, peritonitis, and spondylodiscitis.

Molecular Diagnosis of Tubercular Lymphadenopathy from Fine-Needle Aspirates in Pediatric Patients

OBJECTIVES

The diagnosis of peripheral tubercular lymphadenopathy (TBLN) in pediatric patients is often a challenge because features evident on fine-needle aspiration cytology (FNAC) or tissue biopsy can be deceptive for the reason that they result from an immunological response. This study aimed to evaluate polymerase chain reaction (PCR) for Mycobacterium tuberculosis complex (MTBC) in pediatric patients under clinical suspicion for TBLN and to assess its role in the evaluation of cases cytodiagnosed as reactive lymphoid hyperplasia.

METHODS

This was a cross-sectional study conducted on 45 pediatric patients clinically suspected and unsuspected for TBLN. FNAC, culture on Löwenstein-Jensen medium, and real-time PCR were performed. Comparative values with reference to the culture were calculated.

RESULTS

Cytology had a sensitivity and specificity of 38.5 and 87.5%, respectively. Real-time PCR had a sensitivity and specificity of 84.6 and 81.3%, respectively. Of the 32 cases with a cytodiagnosis of reactive lymphoid hyperplasia, 53% were positive both on PCR and culture for M. tuberculosis; the φ value of 0.93 demonstrated a strong association between these 2 methods.

CONCLUSION

Real-time PCR is useful in detecting MTBC in pediatric patients, and it also helps in the diagnosis of cases missed on FNAC.

Mediastinal and Disseminated Mycobacterium kansasii Disease in GATA2 Deficiency

RATIONALE

Mycobacterium kansasii usually causes chronic pulmonary infections in immunocompetent patients. In contrast, disseminated M. kansasii disease is commonly associated with advanced human immunodeficiency virus infection, but is reported infrequently in other immunocompromised patients.

OBJECTIVES

To identify common clinical manifestations and potential risk factors for M. kansasii infection in patients with GATA2 deficiency.

METHODS

We reviewed M. kansasii disease associated with GATA2 deficiency at one institution and disease associated with primary and other immunodeficiencies reported in the literature.

MEASUREMENTS AND MAIN RESULTS

Nine patients with GATA2 deficiency developed M. kansasii infections. Six patients developed disseminated disease. All patients presented with significant mediastinal lymphadenopathy or abscesses. Seven patients had pulmonary risk factors, including six smokers. The majority of patients had low numbers of neutrophils, monocytes, B cells, CD4+ T cells, and natural killer cells. Other conditions associated with disseminated M. kansasii disease were thymic disorders and IFN-γ/IL-12 defects.

CONCLUSIONS

Disseminated M. kansasii disease involving mediastinal lymph nodes is surprisingly common in GATA2 deficiency, but also occurs in defects of IFN-γ synthesis and response. Disseminated M. kansasii should be considered a marker indicating a need to evaluate for immunodeficiency syndromes.

Cutaneous Tuberculosis Occurring After a Skin Cut in a Child

BACKGROUND

Tuberculosis is a common problem in Turkey, and cutaneous tuberculosis is a rare form of extrapulmonary tuberculosis. Herein, the authors describe a case of cutaneous tuberculosis (lupus vulgaris) occurring after contact with a sheep.

CASE

A 15-year-old boy was admitted to Marmara University School of Medicine Pendik Training and Research Hospital (Istanbul, Turkey) with delayed wound healing on the left index finger and left axillary lymphadenopathy. His medical history was unremarkable except for a wound incurred when he slaughtered a sheep 3 months before. One month after this injury, the patient developed enlargement of the left axillary lymph node on the side of the wounded extremity, and the wound turned a dark black color. The biopsy specimens obtained from the wounded skin and lymph nodes showed granulomatous reaction, but acid-fast bacilli (AFB) could not be shown with Ehrlich-Ziehl Neelsen staining. The patient tested positive in an interferon-gamma release assay. Computerized tomography scans of the thorax were normal, and early morning gastric lavage specimen was negative for AFB. The wound and axillary lymphadenopathy disappeared after institution of anti-tuberculosis therapy.

CONCLUSION

Tuberculosis infection must be considered in chronic skin lesions with granulomatous reaction occurring in countries with high prevalence of tuberculosis.