Bacillus Calmette-Guérin Vaccine-Related Osteomyelitis in Immunocompetent Children in Saudi Arabia: A Narrative Review.

The Bacillus Calmette-Guérin (BCG) vaccine is the most frequently used live-attenuated vaccine worldwide. Since 2002, two BCG vaccination strains, Pasteur 1173 P2 and Tokyo 172-1, have been the mainstay of Saudi Arabian healthcare. In 2005, the Danish 1331 strain was first used as the principal strain in clinical trials. Children can develop osteomyelitis 4-24 months after immunization with the BCG vaccine, an uncommon but serious side effect in immunocompetent children. We conducted this study to review the epidemiology, diagnosis, clinical symptoms, laboratory analyses, imaging features, and management of BCG osteomyelitis in immunocompetent children. Long bone metaphyses and epiphyses are more frequently affected. The diagnosis of BCG osteomyelitis is difficult because the symptoms are vague and subtle, and the duration between presentation and vaccination may range from a few months to a year. Radiography and computed tomography scans for BCG osteomyelitis typically show a devastating lesion with an associated periosteal response. Magnetic resonance imaging frequently reveals a large interosseous abscess indicative of osteomyelitis. There are no current treatment guidelines for BCG osteomyelitis in Saudi Arabia, but antituberculous regimens, particularly isoniazid and rifampicin, have been found to be very effective in previous studies. Although older studies did not favor surgical intervention because of the risk of complications, a few studies performed minor surgical interventions and had good outcomes. As BCG osteomyelitis is an infrequent complication, especially in immunocompetent children, its diagnosis is time-consuming. Therefore, it is critical to inform healthcare workers of this possible complication to make the diagnosis more straightforward and avoid confusion with pyogenic osteomyelitis. As only a few cases have been reported, further studies in Saudi Arabia are required for evidence-based guidelines applicable to actual practice to be established.