J. Endocrinol. Invest. 19: 136-137,1996

CASE REPORT

Kikuchi's disease associated with Hashimoto's thyroiditis S.1. Rubio, T.Sauer Plewinsky, M. Sabatini, and L. Poretsky Divisions of Endocrinology, Departments of Medicine and Pathology, Cabrini Medical Center and S1. Vincent's Medical Center, New York Medical College, New York, N.Y., U.S.A.

ABSTRACT. We describe a unique association of histiocytic necrotizing lymphadenitis (Kikuchi's dis­ease) and chronic lymphocytic (Hashimoto's) thy­roiditis in a patient who presented with significant cervical lymphadenopathy and a gOiter. This case

INTRODUCTION

Histiocytic necrotizing lymphadenitis or Kikuchi's dis­ease is a benign form of lymphadenitis characterized by lymphadenopathy, fever and leukopenia (1). It usu­ally affects young women and resolves spontaneous­ly within one to four months. The diagnosis is based on clinical and histopathological findings, therefore, a biopsy is necessary. Chronic lymphocytic (or Hashimoto's) thyroiditis is the most common inflam­matory thyroid disease. It is autoimmune in origin and is more common in women, often seen between the ages of 30 and 50 years. The typical presentation is a diffuse and firm goiter. Regional lymphatic node en­largement, although infrequent, has been described (3). Although Kikuchi's lymphadenitis has been associated with other autoimmune diseases, like, for example, sys­temic lupus erythematosus (4), it has never been seen, to our knowledge, in patients with Hashimoto's thyroidi­tis. We report the first case of Kikuchi's disease associ­ated with Hashimoto's thyroiditis.

CASE REPORT

A 27-year-old previously healthy female was seen for evaluation of a small and painless goiter. Her thyroid func­tion tests were normal. Since no masses or nodules were identified within the thyroid, a diagnosis of simple goiter was made and the patient was obseNed without any ther­apy. Approximately a month later, she developed ceNi-

Key-words: Kikuchi, lymphadenitis, thyroiditis, Hashimoto, goiter.

Correspondence: Leonid Poretsky, M.D. , The New York, Hospital-Cornell Medical Center, Division of Endocrinology, 525 East 68th Street, F2019, New York, NY 10021 .

Accepted: December 20, 1995.

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illustrates the value of lymph node biopsy combined with the fine needle aspiration of the thyroid in de­termining the nature of the relationship between the goiter and lymphadenopathy.

cal lymphadenopathy and fever without any other clini­cal evidence of a systemic or oropharyngeal infections or connective tissue diseases. Pertinent laboratory stud­ies included a white cell count of 3.4 x 109/L (normal range 3.9 - 11.4), hemoglobin of 127 g/L (119 - 158), hematocrit of 0.37 (0.35 - 0.47) and platelet count of 197 x 109/L (140-440). Her serum electrolytes and liver func­tion tests were normal. A lymphatic node biopsy was con­sistent with histiocytic necrotizing lymphadenitis (Kikuchi's disease) (Fig. 1A and 18). Symptomatic therapy, which included anti-inflammatory measures, was provided. Two months later, she developed tachycardia and was evaluated once again for her thyroid function. Her thy­roid function tests at this time were consistent with hy­perthyroidism: free T4 was 55pmol/L (10-36), T3 by RIA was 5.4nmol/L (1.2-3.4), TSH was .06mU/L (.30 - 5.00), antithyroglobulin antibodies were positive at 1.80 u/ml, antimicrosomal antibodies were positive at 89.6 u/ml (both types of antibodies were measured by immunora­diometric assays at Corning Metpath laboratories, Teterboro, New Jersey, U.S.A.; normal values for both types of antibodies are <0.3 u/ml). Anti-TSH-receptor an­tibodies were 68 u/ml (normal value 0-130 u/ml, Corning Metpath laboratories, Teterboro, New Jersey, U.S.A). The 24 hour 1-123-uptake in the thyroid was low at 0.6%. A thyroid sonogram showed diffuse thyroid enlargement without nodules. The patient was started on propranolol, 20mg three times daily for symptomatic relief of tachy­cardia. This medication was stopped a month later when the palpitations subsided. The following month her thyroid function tests were consistent with hypothyroidism: free T4 was 4pmol/L (10-36), T3 by radioimmunoassay was 1.0 nmol/L (1.2-3.4), TSH was 45.0mU/L (0.30-5.00). Thyroid sonogram showed no change from previous study. The patierJt was started on levothyroxine, 0, 1 mg PO daily with normalization of thyroid function tests. After three months of thyroid hormone replacement the

Kikuchi's disease and thyroiditis

Fig. 1 A/1 B - Microphotography of a paracortical area of a lymph node with Kikuchi's disease or histiocytic necrotizing lymphadeni­tis. Large collection of histiocytes admixed with immunoblasts and karyorrhectic debris are prominent. Neutrophils are conspicuously absent. 100x and 400x

patient was clinically and biochemically euthyroid, but the lymphadenopathy and the goiter persisted. Because of the unclear nature of the relationship between the lym­phadenopathy and the goiter and in an attempt to es­tablish a definitive diagnosis, a fine needle aspiration of the thyroid was performed. Results were consistent with lymphocytic thyroiditis (Fig 2).

COMMENT Hashimoto's thyroiditis is an autoimmune disease which sometimes can be associated with cervicallym­phadenopathy. In some patients, however, the origin of lymphadenopathy can be mistakenly attributed to thy­roiditis, while the lymphadenopathy can be caused by another disease process, as demonstrated by our pa­tient with Hashimoto's thyroiditis and Kikuchi's disease. We cannot be certain whether the association be­tween these two conditions in our patient is purely co­incidental. Kikuchi's disease has been previously as­sociated with other autoimmune diseases like, for ex­ample, systemic lupus erythematosus (4). Lympha-

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Fig. 2 - Microphotography of fine needle aspiration biopsy of the thyroid smear showing numerous dispersed smalllympho­cytes as well as plasma cells. Scattered among these cells are follicular cells in clusters (Papanicolau stain). 100x

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denopathy can also develop in patients with Graves' disease, which is also autoimmune in origin (5). Since Hashimoto's thyroiditis is an autoimmune disease as well, additional clinical and immunological studies may be required to uncover the nature of its associa­tion with lymphadenopathy observed in Kikuchi's dis­ease. We conclude that Kikuchi's disease and autoimmune thyroiditis can coexist. Therefore, in a patient with clin­ical evidence of thyroiditis, the presence of lym­phadenopathy out of proportion to thyroid findings must be investigated with a lymphatic node biopsy. Whenever the nature of an association between a goi­ter and cervical lymphadenopathy is unclear, fine nee­dle aspiration biopsy of the thyroid can help clarify their relationship.

REFERENCES 1. Piccirillo J.F., Lanza D.C., Stasio EA, Maloy P.J.

Histiocytic Necrotizing Lymphadenitis (Kikuchi's Disease). Arch. Otolaryngol Head Neck Surg. 117: 800, 1991.

2. Singer PA Thyroiditis: Acute, Subacute and Chronic (Review). Med. Clin. North. Am. 75: 61 , 1991.

3. Wortsman J., Dietrich J., Apeson J., Folse R. Hashimoto's thyroiditis simulating cancer of the thyroid. Arch. Surg. 116:386,1981 .

4. Dorfman R.F. , Berry G.J . Kikuchi's histiocytic necrotizing lymphadenitis: an analysis of 108 cases with emphasis on differential diagnosis. Semin. Diagn. Pathol. 5: 329, 1988 .

5. Ansell J.E . The blood in thyrotoxicosis. In: Braverman L.E. , Utiger R.D., (Eds.) , Werner and Ingbar's: The Thyroid, ed. 6. J.B. Lippincott, Philadelphia, 1991, p. 785.