Page 101 - ASOP ROT Study Guide

6 . 2 Pseudogout

Pseudogout may mimic gout but usually has a less acute presentation. In this case the cause is the deposition
of a crystal known as pyrophosphate, the origin of which is unknown, on the articular surface of the joint.
Chronic crystal arthroplasty of this kind causes calcification of joint surfaces and the menisci in the knee.
Symptoms may be controlled with anti- inflammatory drugs but long term degeneration is likely.

7. SEPTIC ARTHRITIS

7 . 1 Acute Septic Arthritis

7 . 1 . 1 Etiology

Acute septic arthritis is an infection caused by bacteria which have spread to the joint via the blood from a site of
trivial infection, such as a boil. It may occur very rarely from direct penetration of the joint by a sharp object. In
adults joint infection is rare unless the joint is already damaged, or the immune defense system is abnormal.

7 . 1 . 2 Clinical picture

In children it usually presents with a very unpleasant acute illness during which the child is unwell with a high
temperature. The affected joint is stiff and is hot and tender.

In contrast, adults often have a much less acute illness. The chronically abnormal joint may give the false
impression of a minor upset. The patient remains unwell for many days before presenting with blood poisoning.
Many of these patients die because of the delay in recognizing the condition.

In the relatively rare instance of a young adult presenting with a septic arthritis, often with little constitutional
upset, the most likely cause is gonococcus, which is a type of bacteria commonly associated with venereal
disease.

7 . 1 . 3 Management

Treatment consists of surgery and intravenous antibiotics. The joint should be opened and washed. Antibiotics
should be given according to the type of organism causing the infection. The "first guess" antibiotic should be
an anti-staphylococcal agent in children as this is still the most likely infecting organism. If this treatment is
inadequate then, apart from the risk of a poisoning of the blood stream (septic anemia), the articular cartilage is
at great risk and may disintegrate, leading to fibrous or even bony fusion of the joint.

7 . 2 Chronic

7 . 2 . 1 Etiology

Joint tuberculosis (TB) is a bacterial infection resulting in chronic septic arthritis. It is found world-wide
although mainly in underdeveloped countries. AIDS patients are particularly prone to this chronic illness. The
TB bacteria spread to the joints via the blood. Kidney and joint TB are often found together.

7 . 2 . 2 Clinical presentation

The clinical picture is of chronic ill health, weight loss and considerable muscle wasting around the affected joint.
The radiographs, (produced from X-rays) show marked thinning of the bone.

7 . 2 . 3 Management

Treatment is by drugs and only rarely is surgery necessary. Combinations of antibiotics such as streptomycin,
ethambutol and rifampicin are given for many months.