This is a 21-year-old female with a history of chronic headache for several years with Chiari decompression surgery performed in 2017 and latero-cervical adenopathy diagnosed as lymph node TB on bacteriological, molecular and histological arguments in 2019. GeneXpert MTB/RIF performed on the cervical lymph node came back positive for TB, without resistance to rifampicin. She was then treated at another institution according to the national protocol which includes quadritherapy with isoniazid, rifampicin, ethambutol and pyrazinamide for 2 months followed by bitherapy with isoniazid and rifampicin for 10 months (2RHZE/10RH). The evolution was then marked by the disappearance of the lymph nodes after one year of treatment. Six months after the end of treatment, the patient presented to the emergency room with severe headaches.
Otherwise, no cough, chest pain, fever, or loss of appetite was reported. The patient noted no signs of trismus or difficulty breathing. She reported no known allergies and had no history of smoking or drinking alcohol. On admission, physical examination revealed a body temperature of 36.6  C, a heart rate of 90 beats/min, and a blood pressure of 117/75 mmHg. Palpation of both sides of the neck revealed no tenderness and no lymph nodes were noted. Examination of the oral cavity revealed no pathologic findings, and no posterior pharyngeal wall projections were observed. The lungs were clear on auscultation and no neurologic deficits were noted on initial clinical examination.
The biological workup showed hemoglobin at 12.6 g/l; white blood cell count at 4.8 G/l; and C-reactive protein at 0.8 mg/l. In addition, serologies for human immunodeficiency virus (HIV), hepatitis B, and hepatitis C were negative.
A cerebral CT scan performed as part of the etiological diagnosis fortuitously revealed a peripherally enhanced collection in the retropharyngeal area after injection of contrast medium measuring 19 x 21 mm, associated with an adjacent necrotic adenopathy measuring 10 x 06 mm. (Fig. 1).
A cervical MRI was realized later and confirmed the presence of the retropharyngeal collection. (Fig. 2).
The abscess was drained under local anesthesia. 02 milliliters of pus were aspirated. The specimen was sent for bacteriological analysis for Mycobacterium tuberculosis complex (MTC) and banal germs as well as for pathological study. A molecular study using GeneXpert MTB/RIF (Cepheid, Sunnyvale, CA, USA) resulted in detection of MTC with detection of rifampicin resistance in less than 2 h. In response to this rifampicin resistance, we performed other molecular tests, including GenoType MTBDRplus VER. 2 and GenoType MTBDRsl VER.1 (Hain Lifescience GmbH, Nehren, Germany) on the pus to confirm rifampicin resistance and also to investigate resistance to other anti-TB drugs. It should be noted that this technique is not validated on extrapulmonary specimens directly, although many studies have showed a good correlation with the usual resistance screening methods. The MTBDRplus VER. 2 showed resistance to both rifampicin and isoniazid, while MTBDRsl VER.1 showed resistance only to aminoglycosides.
Direct examination after special Ziehl-Nielsen staining was positive and cultures on Lowenstein-Jensen  (LJ) solid medium and Mycobacteria Growth Indicator Tube (MGIT ) liquid medium were positive after 32 days and 12 days respectively, thus confirming the molecular diagnosis.
A treatment was initiated on the basis of molecular data. The histopathological study confirmed the molecular diagnosis by showing epithelioid and gigantocellular granulomas with caseous necrosis, without histological evidence of malignancy.
Subsequently, the patient was put on a long-term protocol consisting of 6 months of bedaquiline, levofloxacin, linezolid, clofazimine, and cycloserine and 12-14 months of levofloxacin, linezolid, clofazimine, and cycloserine.
After 1 month of treatment, the antibacillary drugs appear to be well tolerated, and the patient is still being monitored.