A Rare Presentation of Acute Multifocal Skeletal Multidrug-resistant Tuberculosis

DISCUSSION

Tuberculosis (TB) involving the musculoskeletal system is unusual and accounts for 5% of skeletal TB in all ages.² Nearly 50% of patients with skeletal involvement have primary pulmonary involvement and are often immunocompromised. Tuberculous osteoarticular lesions arising at two or more locations is multifocal skeletal TB.⁴ Indumathi et al.⁵ has published a case report of a 15-year-old female child who had developed swellings on the right foot in a duration of 1 month and five chest X-rays were suggestive of military TB. In contrast, the patient in our study was immunocompetent with no pulmonary involvement or exposure to TB.

Mycobacterium TB disseminates from the lungs through the lymphohaematogenous course.⁶ These disseminated bacilli lodges in the small terminal arteries of the metaphysis of bones give rise to tuberculous lesions after one year of primary infection.⁴ The bone lesions have four elementary presentations—(1) cystic, (2) infiltrative, (3) focal erosions, and (4) spina ventosa.⁷ Osteoarticular TB, when disseminated, gives rise to multiple foci, which may be destructive and is frequently confused with sarcoidosis, also known as Jungling’s disease, which occurs secondary to primary lung focus. Its onset is subtle, with indeterminate signs and symptoms such as low-grade fever, weight loss, and decreased appetite. Hosalkar et al.⁸ conducted a retrospective study which included 18 children who were treated for tubercular skeletal lesions over a period of 5 years. They found that the average duration of symptoms was 6 months with only four children having a history of contact with active TB patients and five of them had significant weight loss. In our study, the patient had an acute presentation of multiple noncontiguous swellings for 6 days without any history of contact with a TB patient.

Children typically have multiple lesions with involvement of the peripheral skeleton, and primary metaphysis of the long bones. Soft-tissue swellings, tenderness, and limitation of movements are other joint exhibitions. Diverse children’s radiological display of tuberculous bone lesions can mimic numerous conditions, including subacute and chronic osteomyelitis, bone cysts, cartilaginous tumors, osteoid osteoma, and granulomatous lesions, hematological disease, and malignant tumors. Rasool et al.⁷ reviewed the clinical records and radiographs of 42 children with osseous lesions of TB diagnosed and treated at King Edward VIII Hospital, Durban, South Africa, between 1984 and 1999. The majority were in the metaphyses of the long bone, the rest were on the diaphyses, the epiphyses, short tubular bones (hands, feet), flat bones (pelvis, clavicle), and in the small round bones (patella, talus, and navicular). Four basic patterns of bony lesions were seen—the most common type was the cystic type. Our patient presented with similar vague clinical signs and symptoms.

Plain radiographs routinely advised may not show any changes in the early stages of the disease. An MRI is a gold standard to determine osteolytic cystic lesions with or without sclerosis or reactive bone formation. Adults typically have sclerotic lesions compared to children.⁹ A study done by Rasool et al.⁷ published that all children showed good healing with minimal sclerosis.

Indeterminate clinical and radiological findings of these multiple lesions imitate hematological malignancies, rheumatological conditions, pyogenic and mycotic osteomyelitis, eosinophilic granuloma, chronic relapsing multifocal osteomyelitis, neuroblastoma, and secondaries. Multifocal tuberculous involvement of the musculoskeletal system is uncustomary and usually overlooked for malignancy. Fine needle aspiration cytology, tissue biopsy, culture, and sensitivity are essential to distinguish from malignancies.^8,10 In a case report published by Dewan et al.,¹¹ A 3-year-old girl child presented with multiple bony lesions with hepatosplenomegaly and significant pallor, a differential diagnosis of multi-system Langerhans cell histiocytosis, polyostotic fibrous dysplasia, and multifocal TB was considered.¹²

Antitubercular therapy (ATT) for 6–12 months is fundamental and effective in treating 85–90% of cases. Surgery should be considered in 10–15% of cases not responding to ATT. The prognosis is altogether good with precise diagnosis and early management.¹³

Musculoskeletal multidrug-resistant (MDR) TB cases were identified and published more frequently prior to 2013 but such cases weren’t published later. Such an acute and rare presentation of MDR TB skeletal lesions should be considered as a differential diagnosis in the upcoming time.

To conclude, we present a rare case of MDR TB acutely involving multiple musculoskeletal sites in an immunocompetent child without a primary pulmonary lesion and previous exposure to TB. Hence, diagnosing and promptly starting treatment is imperative to prevent any disability.