What is histiocytic necrotising lymphadenitis?
Histiocytic necrotising lymphadenitis is a benign condition presenting with lymphadenopathy, mild fever, and occasionally a rash or other systemic symptoms .
Histiocytic necrotising lymphadenitis is also known as Kikuchi disease, Kikuchi–Fujimoto disease, and histiocytic necrotising lymphadenopathy.
Who gets histiocytic necrotising lymphadenitis?
Histiocytic necrotising lymphadenitis is very rare and predominantly affects young adult Asians, although there have been cases reported worldwide in all races. It is most commonly reported in women [1–4].
What causes histiocytic necrotising lymphadenitis?
The cause of histiocytic necrotising lymphadenitis remains unknown. The histological and clinical presentations suggest either a viral or autoimmune trigger for a T-cell and histocyte immune response .
What are the clinical features of histiocytic necrotising lymphadenitis?
The clinical symptoms and signs of histiocytic necrotising lymphadenitis develop over two to three weeks and then subside over the next 4 months [4–6].
The hallmark of the disease is tender palpable lymph nodes most commonly of the back of the neck, above the collarbones, and in armpits. Typically the lymph node enlargement is unilateral. Generalised lymph node enlargement has been reported in up to 22%.
The most common symptom is fever. Other systemic signs and symptoms include:
Less frequent signs and symptoms are a sore throat, upper respiratory symptoms, hepatosplenomegaly (swelling of the liver and spleen), weight loss, night sweats, nausea, vomiting, and diarrhoea.
What are the cutaneous manifestations of histiocytic necrotising lymphadenitis?
Transient cutaneous manifestations have been reported in up to 40% of patients with histiocytic necrotising lymphadenitis [4,5].
Cutaneous features of histiocytic necrotising lymphadenitis are non-specific, and may include :
- Morbilliform rashes may mimic rubella or a drug-induced eruption
- Facial erythema, sometimes resembling the butterfly rash of systemic lupus erythematosus (SLE)
- Erythematous macules, plaques, and acneiform eruptions on the face
- Indurated papules on the back and arms
- Oropharyngeal redness and ulceration.
How is histiocytic necrotising lymphadenitis diagnosed?
Histiocytic necrotising lymphadenitis is diagnosed on lymph node biopsy; patchy but well-defined necrosis lacking neutrophils and eosinophils within an expanded paracortical area of the lymph node .
Skin biopsy shows upper dermal oedema with a perivascular infiltrate in the dermis and subcutaneous fat. The infiltrate is composed mainly of histiocytes, small lymphocytes, and nuclear debris.
There is no specific blood test for histiocytic necrotising lymphadenitis. Elevation of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), anaemia, leukopenia and leukocytosis have been reported [4,6].
Specific blood tests may be required to exclude another disease, such as ANA for SLE.
What is the differential diagnosis for histiocytic necrotising lymphadenitis?
The clinical differential diagnosis for histiocytic necrotising lymphadenitis includes any disorder that results in lymph node enlargement [4,6].
Infections and non-Hodgkin lymphoma can cause unilateral enlargement of lymph nodes, although in lymphoma tenderness and pain would be uncommon.
Autoimmune disorders such as SLE-related lymphadenopathy need to be considered, as these may show similar clinical and histological features to histiocytic necrotising lymphadenitis.
What is the treatment for histiocytic necrotising lymphadenitis?
Histiocytic necrotising lymphadenitis is self-limiting.
Symptomatic management of tender cervical lymphadenopathy may include paracetamol and non-steroidal anti-inflammatory drugs. Patients with a severe clinical course or relapsing disease may be treated with oral corticosteroids [4,6].
What is the outcome for histiocytic necrotising lymphadenitis?
Histiocytic necrotising lymphadenitis lasts for one to four months. The recurrence rate is 3–4% [4,6].