Kikuchis lymphadenitis : Is biopsy necessary in managing these patients

Kikuchis-Fujimoto’s is a benign, self-limiting, cervical lymphadenitis, fi ne-needle aspiration cytology (FNAC) plays a very important role in the diagnosis and management of these patients. We present a case of 30-year-old female presenting with supraclavicular lymphadenopathy and fever, diagnosed as Kikuchis-Fujimoto’s lymphadenitis on FNAC with no recurrence or development of Lupus lymphadenitis even after 1-year of follow-up. Although Kikuchis-Fujimoto’s is a rare cause of lymphadenopathy, FNAC is an important tool in diagnosing this entity and differentiating from tubercular lymphadenitis and Lupus adenitis. Presence of cresentric nucleated histiocytes engulfed karryorrhectic debris and monocytoid cells aids in the diagnosing. A defi nitive diagnosis made on FNAC can avoid biopsy and unnecessary diagnostic and therapeutic interventions in these patients. However, a look out for recurrence and development of Lupus with regular followup and serological examination is imperative.


INTRODUCTION
Kikuchis-Fujimoto's disease (KFD) or histiocytic necrotising lymphadenitis was fi rst described by Kikuchis, simultaneously by Fujimoto's et al. in 1972. [1,2]Since then, numerous cases have been reported in both Asian and western population.Though a self-limiting disease that resolves on its own within few weeks and months, it is known to recur in 3-4% of cases. [3]Though fi ne-needle aspiration cytology (FNAC) is diagnostic in most of these cases, histopathological examination of the excised node is usually done to confi rm the diagnosis and differentiate from other causes of adenitis.

CASE REPORT
A 31-year-old female presented with fever (low grade, Intermittent), headache, edema, weight loss and pain in the right supraclavicular region of 3 month's duration.There was no history of cough with expectoration/weight loss/skin rash/joint pain or any other swellings in the body.On examination, she was febrile, with multiple nodules in right supraclavicular region.A diagnosis of viral fever with supraclavicular lymphadenopathy and was made, and she was treated symptomatically.Since her symptoms did not subside even after 1 week of treatment, the presumptive diagnosis of tubercular lymphadenitis was made, and laboratory workup was suggested.All her biochemical and hematological investigations were normal except an increase in erythrocyte sedimentation rate (80 mm at the end of 1 st h).A diagnosis of Kikuchis-Fujimoto's Lymphadenitis in necrotizing stage was made.Patient was treated symptomatically along with a low dose of corticosteroid.After 3 weeks of treatment, her swelling subsided and there was no relapse or new symptoms even after 1-year of initial presentation.

DISCUSSION
Kikuchis Lymphadenitis is a rare, benign, self-limiting, immune mediated disorder occurring in young females that resolves on its own. [4]Though Kikuchis Lymphadenitis can be diagnosed on fi ne needle aspiration many prefer Lymph node Biopsy for clinching the diagnosis.
Kuo proposed classifi cation of the histopathological features of KFD into three stages-proliferative, necrotizing and xanthomatous stage.The most common stage is the proliferative phase which is characterized by numerous histiocytes, plasmacytoid monocytes, and a variable number of lymphoid cells, karyorrhectic nuclear fragments and eosinophilic apoptotic debris.
If any degree of coagulative necrosis is there, it is necrotic stage, while foamy histiocytes predominate in the xanthomatous stage.He also suggested that these types may suggest different stages of the disease or may refl ect differences in cause or host reaction. [4]ne-needle aspiration fi ndings may vary depending on the stage of the disease.Most common presentation is the stage of necrotizing adenitis wherein presence of cresentric histiocyte (histiocyte with cresentric nucleus and eosinophilic inclusions in the cytoplasm), macrophages with abundant cytoplasm and phagocytosed karyorrhectic or eosinophilia debris, plasmacytoid monocytes were consistent with Kikuchis lymphadenitis.Though numerous differentials are described, in our country differentials such as such as tuberculosis, Systemic Lupus lymphadenitis are important.
Tuberculosis can be differentiated by presence of cheesy necrosis, granulomas, epithelioid histiocytes admixed with neutrophils and absence of any acid-fast bacilli on Ziehl Neelson staining.While the presence of cresentric histiocytes might be a sensitive and considerable specifi c marker of Kikuchis Lymphadenitis. [5]pus adenitis can have a varied presentation.Kucukardali et al. reported 28 cases of Lupus associated KL, wherein 18 patients were diagnosed with Lupus and KL simultaneously, four had previous diagnosis of lupus, six were diagnosed with lupus after they were diagnosed with KL. [6] Lupus adenitis can be differentiated by presence of polymorphous population of lymphocytes, Hematoxylin bodies and immunoblasts in Lupus adenitis as compared to Kikuchis adenitis.Absence of neutrophils will favor a diagnosis of Kikuchis lymphadenopathy.However, antinuclear antibodies and antidouble stranded DNA antibody in serum will confi rm the diagnosis. [7,8]though histopathology will help us to confi rm the diagnosis, patient will be relieved of the burden of surgery, pain by making a defi nitive diagnosis on aspiration keeping in mind the above fi ndings in India were tuberculosis is more common.However, a follow-up of these patients is absolutely necessary as these patients are known to have recurrences or known to develop Lupus. [9]

CONCLUSION
Diagnosis of KFD is possible on FNAC.Keeping in mind the above cytological features it is possible to make a defi nitive diagnosis and avoid biopsy in these patients.However due to a higher incidence of recurrence and occurrence of Lupus in these patients, regular followup and serological testing is important.
Antinuclear antibody test was negative.International Journal of Medicine and Public Health | Jan-Mar 2015 | Vol 5 | Issue 1