Introduction
Tuberculosis is one of the most important infectious diseases that is considered among the top ten causes of mortality worldwide. According to the reports by the World Health Organization (WHO), about 10 million new cases of tuberculosis were diagnosed in 2018, of which 1 million were children; 1.6 million related mortalities were also reported in the same year. Currently, it has been estimated that one-fourth of the world’s population is suffering from the latent TB infection (LTBI), 5-10% of whom will encounter active TB in future [1-2]. The statistics regarding Mycobacterium tuberculosis (Mtb ) drug resistance is also very worrying; 558,000 rifampicin-resistant cases were specified in that year, 82% of whom were multi-drug resistant TB (MDR-TB). According to this report, Iran is also included among the endemic tuberculosis countries [2-3]. The rate of incidence of tuberculosis in Iran is about 22 per 100,000 and the mortality rate is 3.5 per 100,000. According to the reports, the rate of rifampicin and MDR-TB resistance has been reported in Iran at about 1.3-5% [4-5].
While most of the clinical manifestations of tuberculosis are in the pulmonary basis, however, Mtb is capable of affecting all the organs, which is termed extra-pulmonary TB (EPTB). In this respect, cervical tuberculous lymphadenitis is the most common form of EPTB, accounting for 25-30% of the cases [6]. The incidence rate for the EPTB in Iran has also been reported to be approximately 2.5 cases per 100,000 people per year, which are mainly children [7]. Cervical tuberculosis lymphadenitis (CTL) typically involves the lymph nodes of the jugular, posterior triangle, and supraclavicular region, and the observed clinical manifestations of cervical tuberculosis lymphadenitis include fever, weight loss, rarely coughing, night sweat, chills, malaise, suppurative lymphadenitis, granulomatous inflammation, neck mass (1-3 cm), fistula formation and caseous necrosis. However, cervical tuberculosis lymphadenitis is confused with the diseases such as malignancy, fungal infection, tularaemia, actinomycosis, sarcoidosis, and non-tuberculosis mycobacteria (NTM) lymphadenitis [8-11]. Studies have shown that the accuracy and sensitivity of the diagnosing methods for cervical tuberculosis lymphadenitis, such as Ziehl-Neelson (ZN) staining, microbiological culture and PCR, have little diagnostic value and are not reliable, particularly in the medication-resistant cases. The physician may be mistaken for the misdiagnosis due to failing to respond to the anti-tuberculosis treatment [12-15].
Based on the WHO recommendations, category III tuberculosis has been used since the beginning of 1997 to treat the cervical tuberculosis lymphadenitis cases [9]. The development of drug resistance TB (particularly in TB endemic regions) has led to poor treatment outcomes in recent years [16]. Thus, there is a new alternative treatment beside the anti-TB therapy that has been introduced for adults, which is surgery. These invasive techniques also have their own risks and need to be modified and standardized according to the cervical tuberculosis lymphadenitis guidelines [9,16-17]. According to review of the literature, there are numerous reports about cervical tuberculosis lymphadenitis in children [18-19]. However, there are only 5 reports regarding MDR-CTL infection throughout the worldwide. All of these cases had between 19-35 years of age, who recovered by administration of the second-line anti-TB agents [20-24]. We were informed about the first case of congenital cervical tuberculosis lymphadenitis in a 2-months old infant, who was infected by MDR-Beijing Mtb strain. The aim of the present study was to describe an unusual report of cervical MDR-tuberculosis lymphadenitis in a 2-months age infant from Mashhad, Iran.