Infections

• There are many infections that can cause musculoskeletal problems including bone and joint infection, inflammatory arthritis and reactive arthritis (including acute rheumatic fever and post streptococcal arthritis).  
• Musculoskeletal features may be accompanied by systemic and multi-system features.
• Morbidity is high and there is potential mortality without diagnosis and access to the right specialist care and treatment. 
• There is a wide range of infectious organisms that are be implicated - bacteria, mycobacteria, viruses, fungal diseases and parasitic infections.
• The prevalence, risk factors and manifestations vary around the world. A travel, environmental or occupational history are therefore sometimes relevant.
• Some infections are transmitted by insects (e.g., arbovirus infections - Dengue, Chikungunya and Zika) or ticks (e.g., Lyme Disease) or through contact with animals or unpasteurised milks (e.g., Brucellosis) or following gastrointestinal infection (e.g., Shigella, Campylobacter, Yersinia).
• Some infections are spread through sexual activity (e.g., Gonorrhoea, Syphilis, chlamydia, Human Immunodeficiency Virus [HIV]) or through contact with blood products or intravenous drug abuse (e.g., HIV) or vertical transmission (e.g., pregnancy and HIV).  Sensitive enquiry may be needed to explore risk factors. 
• The presentations of infection are influenced by individual host factors.
• Tuberculosis (TB) must be considered in children who are living in endemic areas or are immunosuppressed (due to disease, co-existent HIV infection or systemic immunosuppressive treatments). 
• This module covers important infections that can result in musculoskeletal features. 
• We include notes on Tuberculosis, Reactive Arthritis, Acute Rheumatic Fever, Post Streptococcal Arthritis, Arboviruses (Dengue, Chikungunya, Zika), HIV, Brucellosis, Lyme Disease, Fungal and Protozoal Infections.
• Septic arthritis and osteomyelitis. 
• Chronic Recurrent Multifocal Osteomyelitis or Chronic Nonbacterial Osteomyelitis.
• The Cases also illustrate key points.
• More information is available from the Centre for Communicable Diseases