Signs

Inflammatory arthritis, enthesitis, dactylitis, and joint distribution provide important clues, as do extraarticular features such as inflammatory bowel disease and uveitis. It is important to look for psoriatic skin lesions, particularly in the groin, umbilical area, hairline, ears, and natal (i.e., intergluteal) cleft. Nail lesions, including pits and onycholysis, as well as the presence of spinal disease, support the diagnosis.

 

Diagnostic Criteria

The diagnosis of psoriatic arthritis is based on the recognition of clinical and imaging features, since there are no specific biomarkers.

 

 

 

 

 

 

 

 

 

Psoriasis is a common skin disease that is associated with multiple coexisting conditions.

The most prevalent coexisting condition, psoriatic arthritis, develops in up to 30% of patients with psoriasis.

The manifestation of psoriasis precedes that of arthritis by 10 years on average, although in 15% of cases, arthritis and psoriasis occur simultaneously or psoriatic arthritis precedes the skin disease.

 

Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.

 

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Content 11

 

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