Микобактериальный цервикальный лимфаденит: этиология, диагностика и лечение.

Human medical condition

The disease mycobacterial cervical lymphadenitis, also known as scrofula and historically as king's evil, involves a lymphadenitis of the cervical lymph nodes associated with tuberculosis as well as nontuberculous (atypical) mycobacteria.

Scrofula is the term used for lymphadenopathy of the neck, usually as a result of an infection in the lymph nodes known as lymphadenitis. It can be caused by tuberculous or nontuberculous mycobacteria. About 95% of the scrofula cases in adults are caused by Mycobacterium tuberculosis, most often in immunocompromised patients (about 50% of cervical tuberculous lymphadenopathy). In immunocompetent children, scrofula is often caused by atypical mycobacteria (Mycobacterium scrofulaceum) and other nontuberculous mycobacteria (NTM). Unlike the adult cases, only 8% of cases in children are tuberculous. With the stark decrease of tuberculosis in the second half of the 20th century, scrofula became a less common disease in adults, but remained common in children. With the appearance of HIV/AIDS, however, it has shown a resurgence, and can affect patients at all stages of the disease.

The most usual signs and symptoms are the appearance of a chronic, painless mass in the neck, which is persistent and usually grows with time. The mass is referred to as a "cold abscess", because there is no accompanying local color or warmth and the overlying skin acquires a violaceous (bluish purple) color. NTM infections do not show other notable constitutional symptoms, but scrofula caused by tuberculosis is usually accompanied by other symptoms of the disease, such as fever, chills, malaise and weight loss in about 43% of the patients. As the lesion progresses, skin becomes adhered to the mass and may rupture, forming a sinus and an open wound. The fatal outcome some patients experienced in earlier times was due to a cheese like presentation of the lungs and the King's Evil lesions. It was also associated with pulmonary tuberculosis. Cervical lymphadenitis is commonly caused by an infection of mycobacteria in the head region. This disease is very inconsistent; cases can have different laboratory findings. Sometimes the disease can occur due to tuberculosis disease. However it is vital that, on a case by case basis, it is determined whether the cause is tuberculous or nontuberculous mycobacteria, as treatment often differs between the two forms.

Diagnosis is usually performed by needle aspiration biopsy or excisional biopsy of the mass and the histological demonstration of stainable acid fast bacteria in the case of infection by M. tuberculosis (Ziehl–Neelsen stain), or the culture of NTM using specific growth and staining techniques.

The classical histologic pattern of scrofula features caseating granulomas with central acellular necrosis (caseous necrosis) surrounded by granulomatous inflammation with multinucleated giant cells. Although tuberculous and non tuberculosis lymphadenitis are morphologically identical, the pattern is somewhat distinct from other causes of bacterial lymphadenitis.

King's Evil was known as a frequent disorder in the 17th century, and was believed to be caused by bad blood coagulating in spongy organs such as the thyroid and the lymph nodes. Physicians also believed the disease could be inherited and could result from parents' untreated venereal infections. The treatment for mycobacterial cervical lymphadenitis consisted primarily of small incisions to remove the surrounding soft tissue and/or the abnormal mass. Until the 18th century, many doctors thought the only way to cure the disease was to be touched by a member of a royal family. In both France and England, the kings who were thought to have an inherited miraculous power to cure the illness, touched crowds of infected people. The 'touchings' began in France during the reign of King Philip I (1060–1108) and in England during the reign of King Henry I (1100–1135). This act of public healing by powerful kings and royal family members encouraged the nickname "King's Evil". After the touching, the sovereign presented the affected person with an angel on a gold plated coin that was to be hung around the infected person by a ribbon. This was used as a way of warding off the disease. This coin could have weighed as much as 5 grams and was considered a touch piece of great value. At age three the English lexicographer Samuel Johnson, for example, was treated for scrofula in this way, touched by Queen Anne and presented with a piece of gold, unfortunately, to no effect. The royal touch and surgical removal were not the only methods of healing employed: Scrophularia nodosa (common name: Figwort), which has nodular roots that resemble the swollen lymph nodes of the affected, was thought to be useful in treating the disease, according to the doctrine of signatures – the plant being hung around the neck of the affected. Figwort does, in fact, contain compounds that can help decrease inflammation, irritation and discomfort.

Treatments are highly dependent on the kind of infection. Surgical excision of the scrofula does not work well for M. tuberculosis infections, and has a high rate of recurrence and formation of fistulae. Furthermore, surgery may spread the disease to other organs. The best approach is to use conventional treatment of tuberculosis with antibiotics. The cocktail drug treatment of tuberculosis (and inactive meningitis) includes rifampicin along with pyrazinamide, isoniazid, ethambutol, and streptomycin ("PIERS"). Scrofula caused by NTM, however, responds well to surgery, but is usually resistant to antibiotics. The affected nodes can be removed either by repeated aspiration, curettage or total excision (with the risk in the latter procedure, however, often causing unsightly scarring, damage to the facial nerve, or both). Many different therapeutic options exist, particularly regarding non tuberculosis mycobacterial infections, such as incision and drainage, aspiration biopsy and chemotherapy. All of these methods have proved to result in a cure of the disease. However different treatments can cause different side effects along the way to recovery. Some of these side effects include facial nerve injury and scarring. Therefore, the course of treatment is tailored to each patient, taking into account their history as well as the severity of infection.

With adequate treatment, clinical remission is practically 100%. In NTM infections, with adequate surgical treatment, clinical remission is greater than 95%. It is recommended that persons in close contact with the diseased person, such as family members, be tested for tuberculosis.

A three year old healthy young female presented with a bilateral cervical lymph node enlarged. The patient was admitted to the hospital after tuberculosis skin test became positive and further examination showed several other enlarged lymph nodes near her neck. At the hospital, she underwent an exploration surgery where they excised part of her presented lymph node and drained her retropharynx. The drained retropharynx grew methicillin resistant Staphylococcus epidermidis and Streptococcus mitis. After these findings, the patient received oral linezolid for ten days and had antimicrobial drug therapy for 14 days. Once the patient returned for a follow up appointment, the lymph node had only slightly decreased in size. Due to this, it had to be completely removed from her neck. Bacterial cultivation of tissue from the excised lymph node resulted in the growth of "atypical Mycobacteria", which were identified by 16S gene sequencing as Mycobacterium florentinum. After she recovered and went home, there were no repeat signs that the infection was back for over a year.