 Good evening everyone. We are back again with the case of the month. A 25-year-old female presented with vague history of neck pain. MRI with contrast of brain including the base of skull was asked for. The MR showed heterogeneous altered signal intensity lesions involving the basis venoid, left pterygoid plates including the occipital condyles with associated mild soft tissue component. These lesions showed diffusion restriction, heterogeneous enhancement on post-contrast study with multiple areas of peripheral ring enhancement and central necrosis. In addition, localizer sequences of thorax were obtained which showed an expansile lesion involving the anterior aspect of right third rib. CT cuts of the base of the skull showed permeative osteolytic lesions in the mentioned bones with no evidence of matrix mineralization. In view of the lesion involving right third rib, CT screening of chest and abdomen was done. CT showed expansile leitic lesion involving the rib. A permeative leitic lesion was seen in spinous process of D11 vertebra. Leitic lesions showing a radiolucent rim and central dense sclerotic bone were seen in left pubic bone and right iliac bone consistent with button sequestrum. Erosions and irregularity were seen along the articular aspects of right sacroiliac joint consistent with sacroiliatus. The cranial vault was normal. Lung fields were clear with no evidence of medastinal or hyalurrimphidinopathy. Domen and Pelvis showed no obvious lesion on the plain CT. Permeative leitic lesions in base of skull can be seen in osteomyelitis. Similar lesions can also be seen in metastasis. Although not common, similar lesions have been described in eosinophilic granuloma or Langerhensel histiocytosis as well. Button sequestrum has typically been described in tuberculosis and eosinophilic granuloma or Langerhensel histiocytosis. Unilateral sacroiliatus involving the right SI joint in this case would be typically seen in infective sacroiliatus. Expansile leitic lesion involving the anterior aspect of right third rib can be seen in multiple etiologies such as osteomyelitis, eosinophilic granuloma, metis, fibrous dysplasia among other etiologies. On the basis of all these findings, multiple lesions in multiple locations, differential diagnosis in decreasing order of their likelihood were multifocal osteomyelitis, histiocytosis and metastasis. Myeloma was excluded as no lesions were seen in the skull vault or in the mandible. The patient was sent back to us for FNAC which revealed pus. No acid-fast bacilli were seen on microscopic examination. The sample was sent for CB NAT which is a PCR-based examination for tuberculosis and the report came back positive for tuberculosis. The take-home message from this case would be not all multifocal leitic lesions are metastasis or myeloma. Localizer sequences on MRI and CT screening of other parts can yield a great deal of information and help in narrowing down to probable differential diagnosis. Thank you.