Pathogenic role and diagnostic utility of interferon-α in histiocytic necrotizing lymphadenitis.

PURPOSE: Histiocytic necrotizing lymphadenitis (HNL) is an inflammatory disease of unknown etiology clinically characterized by painful lymphadenopathy. This study aimed to investigate the role of interferon (IFN)-α in the pathogenesis of HNL and the clinical significance of serum IFN-α levels for the diagnosis and monitoring of HNL disease activity. METHODS: This study enrolled 47 patients with HNL and 43 patients with other inflammatory diseases that require HNL differentiation including malignant lymphoma (ML), bacterial lymphadenitis, and Kawasaki disease. Expression of IFN-stimulated genes (ISGs) and MX1 in the lymph nodes was measured by real-time quantitative reverse transcription polymerase chain reaction and immunofluorescence staining, respectively. Enzyme-linked immunosorbent assay was used to quantify serum cytokine levels. The results were compared with the clinical features and disease course of HNL. RESULTS: Patients with HNL had a significantly elevated ISG expression in the lymph nodes compared with those with ML. MX1 and CD123, a specific marker of plasmacytoid dendritic cells (pDCs), were colocalized. In patients with HNL, serum IFN-α levels were significantly elevated and positively correlated with disease activity. The serum IFN-α level cutoff value for differentiating HNL from other diseases was 11.5 pg/mL. CONCLUSION: IFN-α overproduction from pDCs may play a critical role in HNL pathogenesis. The serum IFN-α level may be a valuable biomarker for the diagnosis and monitoring of disease activity in patients with HNL.

Kikuchi-Fujimoto Disease Preceding Overlap Syndrome of Sjögren's Syndrome and Systemic Lupus Erythematosus: Literature Review Based on a Case Report.

Kikuchi-Fujimoto disease (KFD) is a benign, self-limiting histiocytic necrotizing lymphadenitis systemic disorder with unknown etiology. KFD has been known for half a century, but difficulties in distinguishing it remain. Its diagnostic significance is related to the increasing prevalence of KFD with autoimmune diseases in various timeframes. Systemic lupus erythematosus (SLE) is the most prevalent autoimmune connective tissue disease (AICTD) appearing alongside KFD. An 18-year-old female presented with acute muscle weakness, shortness of breath, fever, and significant weight loss for 5 months before admission. Pain and morning joint stiffness had been felt for 9 months. One year ago, she lumped her right neck and was diagnosed with KFD from the excision biopsy and immunohistochemical staining (CD68). Creatine-kinase enzymes and C-Reactive protein were elevated with a high anti-Ku and anti-Jo-1 negative level. There was a low level of complements, high anti-nuclear antibody titer, with positive anti-SS-A. Sialometry and Schirmer test showed reduced salivary and lacrimal gland production. We diagnosed this patient as having an overlap syndrome preceded by KFD. The AICTD involved was Sjögren's syndrome and SLE. Although KFD is considered a self-limiting disease, its occurrence should be noticed regarding the possibility of other autoimmune conditions. KFD usually coincides with AICTD, although it could also precede or occur afterward. This case is reported to raise awareness of the overlap syndrome preceded by KFD.

The significance of T-BET-positive CD8 T-cells with diminished CD5 expression in Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare condition characterized by benign localized lymphadenopathy and clinical symptoms such as fever, sore throat, odynophagia, and leukopenia. Though the etiology of KFD is unknown, this condition is similar to viral infection, including increased infiltration of activated plasmacytoid dendritic cells. KFD exhibits three histological phases that reflect its progression status: proliferative, necrotic, and xanthomatous lesions. The expression loss of pan T-cell markers, such as CD2, CD5, and CD7, of infiltrating T-cells is observed in KFD cases, complicating the distinction from T-cell lymphoma. However, reports on the loss of their expression in KFD have been limited. Furthermore, the precise population of the T-cell subset in KFD is still unclear. Here, we focused on surface markers and transcription factors for T-cell differentiation and analyzed them immunohistochemically in 46 KFD cases. We observed diminished CD5 expression of CD8-positive (CD5dim CD8+) T-cells in the proliferative lesion of KFD cases. Furthermore, these CD5dim CD8+ T-cells expressed T-BET, a master regulator of type 1 helper T-cells. The upregulation of T-BET and downregulation of CD5 in CD8+ T-cells causes dysregulated activation and proliferation of CD8+ T-cells, potentially contributing to the unique histopathological features of KFD. Recognizing the frequent infiltration of T-BET-positive CD5dim CD8+ T-cells in KFD is important for distinguishing it from mature T-cell lymphoma. Our findings suggest that the immune response in KFD shares similarities with viral infections and highlight the importance of characterizing T-BET-positive CD5dim CD8+ T-cell populations for understanding KFD pathogenesis.

Kikuchi-Fujimoto disease following SARS-CoV-2 infection: A rare disease with increased incidence during the COVID-19 pandemic?

Kikuchi-Fujimoto Disease (KFD), also known as Kikuchi disease or Kikuchi histiocytic necrotizing lymphadenitis, is a rare and self-limiting condition characterized by cervical lymphadenopathy and fever, primarily affecting young Asian adults. The aetiology of KFD remains unknown, although various infectious agents have been suggested as potential triggers. With the emergence of the COVID-19 pandemic, cases of post-COVID-19 KFD and post-COVID-19 vaccine KFD have been reported. In this article, we present the first case of post-COVID-19 KFD in Hong Kong. A 24-year-old man developed fever and painful neck swelling 1 month after recovering from COVID-19. Diagnostic evaluation, including ultrasound-guided fine needle aspiration cytology (FNAC), confirmed the diagnosis of KFD. The patient's symptoms resolved spontaneously with supportive care. This case underscores the importance of considering KFD as a potential differential diagnosis in patients presenting with cervical lymphadenopathy and fever following COVID-19 recovery or vaccination.

Clinical features and recurrence predictors of histiocytic necrotizing lymphadenitis in Chinese children.

OBJECTIVES: To characterize the clinical features and to identify the predictors of recurrence of histiocytic necrotizing lymphadenitis (HNL) in Chinese children. STUDY DESIGN: This study retrospectively analyzed the clinical characteristics, laboratory and pathological findings, and recurrence status of children diagnosed with HNL at a single center in China from January 2018 to May 2023. Logistic regression analysis was employed to identify predictors of HNL recurrence. RESULTS: 181 Chinese children with histopathologically confirmed HNL were enrolled (121 males and 60 females). The mean age was 9.3 ± 2.9 years. The most prominent clinical features were fever (98.9%) and cervical lymphadenopathy (98.3%). Aseptic meningitis was the most frequent complication (38.5%), while hemophagocytic lymphohistiocytosis and autoimmune disease were rare (1.7% and 1.2%, respectively). Recurrence occurred in 12.7% of patients. Erythrocyte sedimentation rate (> 30 mm/h) was the significant predictors of HNL recurrence, with odds ratios of 6.107, respectively. CONCLUSION: Our study demonstrates that fever and cervical lymphadenopathy are the most frequent clinical manifestations of HNL in Chinese children, which often coexist with aseptic meningitis. HNL patients with risk factors require follow-up for recurrence.

Kikuchi disease complicated with aseptic meningitis following COVID-19 Vaccination: a case report.

BACKGROUND: Kikuchi Fujimoto disease is a rare self-limiting disorder mainly affecting young Asian females. The typical presentation is unexplained fever with associated cervical lymphadenopathy. It can mimic many sinister diseases such as lymphoma, tuberculosis, and systemic lupus erythematosus. Aseptic meningitis due to Kikuchi disease is extremely rare, and majority were reported from Japan. There have been no published cases of aseptic meningitis due to Kikuchi disease in Sri Lanka. CASE PRESENTATION: A 29 years old Sri Lankan female presented with a prolonged fever for three weeks with an associated headache for five days duration. She developed painful cervical lymphadenopathy during the hospital stay. She has been previously well and had been vaccinated against COVID-19 six weeks before. Her lumbar puncture showed lymphocytic pleocytosis with marginally elevated protein levels and reduced ratio of serum to CSF sugar. Lymph node biopsy was consistent with necrotizing lymphadenitis. She was subsequently diagnosed with Kikuchi disease complicated with aseptic meningitis. She responded to corticosteroids well and had an uneventful recovery. CONCLUSION: Kikuchi disease is a rare self-limiting disorder that can be complicated with aseptic meningitis on infrequent occasions. Other conditions such as tuberculosis, lymphoma, systemic lupus erythematosus, and adult-onset Still's disease should be considered as differential diagnoses. Knowledge of Kikuchi disease and its complications will prevent unnecessary investigations which delay the early diagnosis and treatment.

Kikuchi-Fujimoto disease, simultaneously diagnosed with systemic lupus erythematosus in an Arabic female: an agonizing combination.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare, benign condition affecting young Oriental-Asian females. It is characterized by fever and tender cervical lymphadenopathy with an unclear aetiology, and in most longitudinal reviews, KFD occurs before systemic lupus erythematosus (SLE). Herein, the case of a 28-year-old Kuwaiti female without any relevant past medical history, who was simultaneously diagnosed with KFD and SLE following an Ebstein-Barr virus infection, is reported. The patient was treated with oral prednisolone, hydroxychloroquine, cyclosporin, and belimumab and her response was clinically and biochemically favourable. Although KFD is prevalent in Asian populations, it may affect all races. Early diagnosis of KFD is difficult, particularly when simultaneously diagnosed with SLE, but crucial to preventing inappropriate therapy. Clinicians need to know about this rare disease, especially when patients present with fever and swollen lymph nodes, due to a risk of misdiagnosis with tuberculosis or lymphoma, as these are more often thought to be the cause of such symptoms.

Optic Neuritis in a Pediatric Patient with Kikuchi-Fujimoto Disease: A Case Report and Review of the Literature.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare, benign, and self-limiting condition characterized by lymph node inflammation. While KFD is rarely associated with ocular manifestations, our case report highlights bilateral optic neuritis in a 13-year-old male patient with KFD. We also provide a comprehensive review of similar cases in the literature.

Kikuchi-Fujimoto Disease: A Rare Presentation in a Young Male.

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare benign condition characterized by cervical lymphadenopathy and constitutional symptoms mimicking tuberculosis. We present the case of a 22-year-old male who presented with fever, dry cough, loss of appetite, multiple joint pains for 15 days, and loss of weight for one month. Physical examination revealed palpable cervical, occipital, axillary, and inguinal lymphadenopathy, and laboratory investigations were within normal limits except for raised erythrocyte sedimentation rate (ESR). Contrast-enhanced computed tomography (CECT) showed mediastinal lymphadenopathy with no pleuroparenchymal abnormality of the lung. Excision biopsy of a cervical lymph node confirmed necrotizing lymphadenitis consistent with KFD. The patient was treated with nonsteroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids, resulting in the resolution of symptoms and regression of lymphadenopathy. This case signifies the importance of considering KFD in the differential diagnosis of lymphadenopathy and highlights the significance of histopathological evaluation for accurate diagnosis and management guidance.

Kikuchi-Fujimoto disease evolves into lupus encephalopathy characterized by venous sinus thrombosis: a case report.

Kikuchi-Fujimoto disease (KFD) is a benign, self-limiting illness that can progress to systemic lupus erythematosus (SLE) in approximately 30% of cases. Neurological injuries can occur in both diseases, albeit with distinct presentations. Venous sinus thrombosis is a serious cerebrovascular complication in patients with neuropsychiatric SLE but is rarely observed in patients with KFD. The involvement of various antibodies, particularly antiphospholipid antibodies, can cause vascular endothelial cell injury, resulting in focal cerebral ischemia and intracranial vascular embolism in SLE. However, there are cases in which thrombotic pathology occurs without antiphospholipid antibody positivity, attributed to vascular lesions. In this report, we present a case of KFD and lupus encephalopathy featuring cerebral venous sinus thrombosis, despite the patient being negative for antiphospholipid antibody. We also conducted a comparative analysis of C3 and C4 levels in cerebrospinal fluid (CSF) and peripheral blood, along with the protein ratio in CSF and serum, to elucidate the pathological changes and characteristics of lupus encephalopathy.

Kikuchi-Fujimoto Disease: A Case Report of Prolonged Fever and Lymphadenopathy in a Young Girl.

Kikuchi-Fujimoto disease (KFD) is a benign and self-limited disorder that usually presents with regional cervical lymphadenopathy and fever. We report a case of a 12-year-old female who complained of fever, night sweating, significant weight loss, and tender right cervical lymph node enlargement for 2 months. A full workup including laboratory tests and imaging studies, an excisional biopsy, and histopathological analysis were done, and the diagnosis of KFD was confirmed. The patient was treated with analgesia and oral prednisolone, resulting in good improvement. A high degree of clinical suspicion is imperative for physicians, given the rarity of the disease and the associated diagnostic challenges.

Kikuchi-Fujimoto disease during early pregnancy.

Kikuchi-Fujimoto disease (KFD) is rare during pregnancy. It is characterized by necrotizing lymphadenitis and often occurs in young Asian women. We report a case of KFD during pregnancy, which was difficult to diagnose. A 37-year-old pregnant female (gestational week [GW] 7+5) was admitted to our hospital because of hyperemesis gravidarum. On the eighth day of hospitalization (GW 8+6), she suddenly developed a fever (38.0°C) with skin rash and posterior pharynx redness. Blood tests showed pancytopenia and abnormal liver function. The patient was misdiagnosed with severe Epstein-Barr virus infection and administered with prednisolone. Subsequently, cervical lymphadenopathy was observed, and biopsy results led to the diagnosis of KFD. Thereafter, her symptoms improved, and she was discharged at GW 13+4. KFD must be included as a differential diagnosis for patients with fever, abnormal liver function, and pancytopenia during pregnancy.

Histiocytic necrotizing lymphadenitis with hemophagocytic lymphohistiocytosis in adults: A single-center analysis of 5 cases.

BACKGROUND: Histiocytic necrotizing lymphadenitis (HNL) is a self-limited inflammatory disease of unknown pathogenesis. A very small fraction of patients with HNL could develop hemophagocytic lymphohistiocytosis (HLH), a hyperinflammatory disorder. These patients are diagnosed as HNL with HLH (HNL-HLH). HNL-HLH in the pediatric population has been systemically studied, however, the clinical, laboratory, and radiological features and outcomes of adult patients with HNL-HLH remain to be explored. We aimed to explore the clinical, laboratory, and radiological features and outcomes of adult patients with HNL-HLH. METHODS: We collected the clinical data of patients with HNL-HLH admitted to the First Affiliated Hospital of Nanjing Medical University from October 2010 to June 2015. All the patients underwent lymph node biopsy and have a pathological diagnosis of HNL. The age, gender, clinical presentation, lymph node signs, laboratory findings and imaging data, and pathological findings of the patients were collected. RESULTS: In this study, we reported five adult patients with HNL-HLH. All five patients showed enlarged lymph nodes and prolonged fever. Laboratory findings were consistent with the diagnosis of HLH. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) showed enlarged lymph nodes with increased FDG uptake and splenic hypermetabolism could be present. All the patients responded well to corticosteroids and had a good prognosis. Two of the five patients were diagnosed with systemic lupus erythematosus during the follow-up. CONCLUSIONS: Our study demonstrated that adult patients with HNL-HLH showed distinct clinical, laboratory, and radiological features. And the prognosis is good and patients could be managed with steroids and supportive care.

Unilateral gluteal myositis as a unique presentation in mesenteric Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease (KFD) is a self-limiting disease, characterised by fever and cervical lymphadenopathy. Lymphadenopathy without cervical lymph node involvement is rare and may mimic lymphoma. Although KFD can be associated with extranodal involvement, muscle involvement has not been reported. Herein, we report a novel case of unilateral gluteal myositis associated with mesenteric KFD in a patient who presented with persistent fever and right hip pain. Radiological imaging revealed an inflammatory lesion on the right gluteal muscle and multiple enlarged abdominal lymph nodes. No cervical lymphadenopathy was observed. A mesenteric lymph node biopsy was performed, and the histopathological findings led to a diagnosis of KFD. By day 29, the patient's body temperature gradually returned to normal without any therapeutic intervention. Follow-up radiological imaging showed resolution of the gluteal lesion and a significant decrease in abdominal lymph node size. Considering the clinical course, the unilateral myositis may have developed as an extranodal involvement of KFD. Even if the clinical findings appear unrelated to those of KFD, a differential diagnosis that includes KFD should be considered in patients with unknown origin of fever.

Explore the Diagnosis and Treatment of Histiocytic Necrotizing Lymphadenitis Based on Insidious Pathogen Warm Disease Theory / 浙江中医药大学学报

[Objective]To explore the etiology,pathogenesis and clinical treatment of histiocytic necrotizing lymphadenitis(HNL)based on the insidious pathogen warm disease theory.[Methods]To analyze the etiology,pathogenesis,characteristics of symptoms and transmission of the disease in Chinese medicine,and summarize the treatment principles based on the descriptions about insidious pathogen warm disease in ancient literature and modern researches on HNL,and cite a clinical case for verification.[Results]The pathogenesis of the HNL is mainly characterized by deficient healthy Qi leading to latent evil.The specific manifestation is that exogenous evils are latent in the Moyuan,which causes Yang Qi to be blocked and depressed and turns into heat.Evil heat spreads from the Moyuan to the Shaoyang tri-Jiao,leading to the generation of phlegm,static blood,turbid evil and toxin in the body,which in turn leads to disease.In terms of treatment,supporting healthy Qi and eliminating the evil is regarded as the law of treatment,and the emphasis is eliminating the evil.Aiming at the three pathogenetic links of latent evil,depressed heat and internal production of pathological products,the following treatment principles are formulated:expelling evils from Moyuan,dredging tri-Jiao and promoting the flow of Qi to make the evil heat go out,clearing away endogenous pathological products,removing toxin and dispersing knots.The focus of supporting healthy Qi is the protection of Qi and Yin as well as recuperation after recovery,which prevents evil Qi from remaining and causing the disease to reoccur.The medical case cited was a patient with HNL treated by applying the theory of insidious pathogen warm disease.Damp-heat and toxin brewing,phlegm combined with static blood was the traditional Chinese medicine(TCM)pattern of this case.The the prescriptions were based on Shengjiang Powder combined with Sanren Decoction,and Ganlu Xiaodu Pill successively,added and subtracted according to the syndrome,and the case achieved a significant effect.[Conclusion]The effect of treating HNL based on the insidious pathogen warm disease theory is quite good,which can provide new ideas and methods for the diagnosis and treatment of HNL.

Case Report: Acute abdomen and large mesenteric mass as another face of multisystem inflammatory syndrome in an adolescent child: measure twice, act once!

Introduction: During the Covid-19 era, acute abdomen and mesenteric lymphadenopathy were encountered as frequent mimic of appendicitis. This phenomenon can further complicate the diagnosis of acute abdominal conditions, not solely due to bacterial or viral intestinal infections but also attributable to post-infectious acute inflammatory states resulting in either undertreatment of inflammatory conditions or unnecessary surgery. Case presentation: In this case study, we present the case of an 11-year-old female who initially presented with fever and right lower quadrant abdominal pain, raising concerns of appendicitis. However, upon further investigation, it was revealed that she harbored a sizable mesenteric mass. Subsequent biopsy results unveiled a significant necrotic mesenteric lymphadenitis. Notably, this patient fulfilled the criteria for Multisystem Inflammatory Syndrome in Children (MIS-C), a condition that manifested following persistent postoperative fever. Remarkably, the patient exhibited a highly favorable response to the treatment administered. This clinical scenario presents an atypical manifestation of MIS-C, as the patient displayed a substantial mesenteric mass alongside symptoms mimicking appendicitis, within the context of an acute abdomen. Conclusion: Clinicians should consider MIS-C and other post-infectious inflammatory conditions in mind when diagnosing acute abdominal cases. The presented case underscores the importance of recognizing atypical presentations of MIS-C that can mimic appendicitis, sometimes necessitating surgical resection of a large lymph node. We propose diagnostic flow chart to aid in the differentiation of acute bacterial appendicitis from MIS-C.

Kikuchi-Fujimoto's Disease: A Rare and Underdiagnosed Condition with Possible Renal Involvement.

Kikuchi-Fujimoto disease (KFD), or Histiocytic Necrotizing Lymphadenitis, is a rare disease, with worldwide distribution but is best known in Japan and South Asia. The most common feature is cervical lymphadenopathy, accompanied by tenderness or high fever, with night sweats, but it can also be asymptomatic or with a very wide range of symptoms. The diagnosis is histopathological, on excisional biopsy. The Kikuchi-Fujmoto disease can mimic lymphoma but also tuberculosis and some autoimmune diseases, or be associated with them. Nephrologists need to be aware of it, considering the potential renal involvement. The association with systemic lupus erythematosus (SLE) is the most frequent but not the only one. Early diagnosis of this disease can prevent unnecessary investigations and aggressive therapies.

Case report: Kikuchi-Fujimoto disease: unveiling a case of recurrent fever and enlarged cervical lymph nodes in a young female patient with a literature review of the immune mechanism.

The inflammatory response to viral infection is an important component of the antiviral response, a process that involves the activation and proliferation of CD8+ T, CD4+ T, and dendritic cells; thus, viral infection disrupts the immune homeostasis of the organism, leading to an increased release of inflammatory factors. Kikuchi-Fujimoto disease (KFD) is an inflammatory self-limited disorder of unknown etiology, and it is generally believed that the pathogenesis of this disease includes two aspects: viral infection and autoimmune response. Various immune cells, such as CD8+ T lymphocytes, CD4+ T lymphocytes, and CD123+ plasmacytoid dendritic cells, as well as the cytokines they induce and secrete, such as interferons, interleukins, and tumor necrosis factors, play a crucial role in the pathogenesis of KFD. In this article, we present a case study of a young female patient from China who exhibited typical symptoms of lymph node inflammation and fever. The diagnosis of KFD was confirmed through a lymph node biopsy. She presented with elevated ESR, IL-6, and IFN-γ. Viral markers showed elevated IgG and IgM of cytomegalovirus (CMV) and elevated IgG of Epstein-Barr virus (EBV), while changes occurred in the CD4+ T and CD8+ T cell counts. Eventually, the patient achieved disease relief through steroid treatment. Based on these findings, we conducted a comprehensive review of the involvement of viral infection-induced inflammatory response processes and autoimmunity in the pathogenesis of Kikuchi-Fujimoto disease.

A Case Report of Kikuchi Fujimoto Disease as an Antecedent Illness of Systemic Lupus Erythematosus in a Male.

Kikuchi Fujimoto disease (KFD) is a rare benign self-limiting condition described in young females characterized by lymphadenopathy and fever. It has been associated with several infective and autoimmune diseases, among which systemic lupus erythematosus (SLE) is relatively common. Kikuchi disease could occur either as a proceeding illness or as a coexisting illness with SLE. The presence of necrotizing lymphadenitis is appreciated in the histological specimen to confirm the diagnosis. Anti-nuclear antibody (ANA) positivity implicates a possible correlation with SLE or recurrence of the pre-existing disease. This clinical presentation needs to be evaluated thoroughly to prevent misdiagnosis and inappropriate treatment. Although Kikuchi disease generally warrants supportive treatment, steroids and immune therapy play a role in treating this persistent and recurrent disease. Long-term surveillance is mandatory for the early detection of sinister pathologies.