psoriatic arthritis , anklylosing spondylitis, reactive arthritis & septic arthritis Flashcards
(144 cards)
1
Q
What percentage of people with psoriasis develop Psoriatic Arthritis (PsA)?
A
Approximately 8% of individuals with psoriasis develop Psoriatic Arthritis (PsA).
2
Q
At what age does Psoriatic Arthritis commonly begin?
A
Psoriatic Arthritis commonly begins between the ages of 30 and 50.
3
Q
What percentage of PsA patients can have the condition without psoriasis?
A
10-15% of patients can have Psoriatic Arthritis without having psoriasis.
4
Q
What is dactylitis, and how often does it occur in PsA patients?
A
Dactylitis is a distinctive sausage-like swelling affecting one or two digits, occurring in around 25% of patients.
5
Q
Name some features in the history and examination of Psoriatic Arthritis.
A
- Personal or family history of psoriatic rash on extensor surfaces<br></br>- Joint involvement in hands and feet<br></br>- Dactylitis<br></br>- Eye disease<br></br>- Nail changes (pitting, yellowing, ridges, oncholysis)<br></br>- Enthesopathy (including Achilles tendonitis)
6
Q
What are the patterns of presentation in Psoriatic Arthritis?
A
- Symmetrical polyarthritis (20–40%)<br></br>- Asymmetric oligoarthritis (30–55%)<br></br>- Distal interphalangeal joint disease (7–17%)<br></br>- Arthritis mutilans (5%)<br></br>- Spondylitic pattern +/– sacroiliitis (5–30%)
7
Q
Describe arthritis mutilans and its characteristics.
A
Arthritis mutilans is an aggressive and destructive form of Psoriatic Arthritis affecting 5% of patients. It involves the reabsorption of bone, collapse of soft tissue, and telescoping of the digits.
8
Q
What blood markers are raised in Psoriatic Arthritis, and what is the status of rheumatoid factor (RF)?
A
Raised inflammatory markers are present, but rheumatoid factor (RF) is negative in Psoriatic Arthritis.
9
Q
What imaging modalities are used for investigating Psoriatic Arthritis?
A
- X-ray: Detects joint damage, marginal erosions, ‘whiskering’, osteolysis, and enthesitis.<br></br>- MRI: Detects early inflammatory changes.<br></br>- Ultrasound: Detects enthesitis and synovitis.
10
Q
Name some non-medical management options for Psoriatic Arthritis.
A
Physiotherapy, occupational therapy, orthotics, and chiropodist are non-medical management options.
11
Q
List some symptomatic medical treatments for Psoriatic Arthritis.
A
- Corticosteroids/joint injections<br></br>- Topical steroid eyedrops
12
Q
What are the three categories of disease-modifying medications used for Psoriatic Arthritis?
A
- NSAIDs<br></br>2. csDMARDs (e.g., methotrexate, sulfasalazine, leflunomide)<br></br>3. Anti-TNF (bDMARD) in severe cases unresponsive to NSAIDs and methotrexate.
13
Q
Provide examples of biologics used in the treatment of Psoriatic Arthritis.
A
- Secukinumab - bDMARD, anti-IL17<br></br>2. Targeted synthetic DMARDs (e.g., tofacitinib - Janus kinase inhibitor) used after the failure of csDMARDs +/– bDMARDs.
14
Q
What are the first-line disease-modifying medications for Psoriatic Arthritis?
A
First-line disease-modifying medications include NSAIDs and csDMARDs.
15
Q
What is Psoriatic Arthritis, and how is it associated with psoriasis?
A
Psoriatic arthritis is an inflammatory arthritis associated with psoriasis. It ranges in severity from mild joint stiffness to complete joint destruction in arthritis mutilans.
16
Q
What percentage of patients with psoriasis develop Psoriatic Arthritis, and when does it typically occur?
A
Psoriatic arthritis occurs in 10-20% of patients with psoriasis, usually within 10 years of developing the skin condition. It can precede skin changes and may occur at any age, most commonly in middle age.
17
Q
What are the patterns of Psoriatic Arthritis, and which ones are the most common?
A
There are five recognized patterns: Asymmetrical oligoarthritis, Symmetrical polyarthritis, Distal interphalangeal predominant pattern, Spondylitis, and Arthritis mutilans. The most common patterns are Asymmetrical oligoarthritis and Symmetrical polyarthritis.
18
Q
Describe the features of Arthritis mutilans, the most severe form of Psoriatic Arthritis.
A
Arthritis mutilans is the most severe form, affecting the phalanges (bones of fingers and toes). It involves osteolysis (bone destruction) around the joints, leading to progressive shortening of the digits. The telescoping digit appearance results from skin folding as the digit shortens.
19
Q
How can Psoriatic Arthritis be distinguished from rheumatoid arthritis based on joint involvement?
A
Psoriatic arthritis tends to affect the distal interphalangeal (DIP) joints and the axial skeleton, distinguishing it from rheumatoid arthritis. Rheumatoid arthritis typically does not affect these joints.
20
Q
What are some signs of Psoriatic Arthritis observed in the skin and nails?
A
Signs include psoriasis plaques on the skin, nail pitting, onycholysis (nail separation from the nail bed), dactylitis (inflammation of the entire finger), and enthesitis (inflammation at tendon insertion points into bone).
21
Q
What is the Psoriasis Epidemiological Screening Tool (PEST), and how is it used in screening for Psoriatic Arthritis?
A
PEST is a screening tool involving questions about joint pain, swelling, arthritis history, and nail pitting. A high score triggers a referral to a rheumatologist, aiding in the identification of Psoriatic Arthritis in patients with psoriasis.
22
Q
What are the characteristic x-ray changes seen in Psoriatic Arthritis?
A
X-ray changes include periostitis (inflammation of the periosteum), ankylosis (fusion of bones at the joint), osteolysis (bone destruction), and the “pencil-in-cup” appearance, associated with arthritis mutilans, featuring erosion and a cup-like appearance in the joint.
23
Q
What is the classic x-ray finding in the digits associated with arthritis mutilans?
A
The “pencil-in-cup” appearance is the classic x-ray finding in the digits. It involves erosion of bones at the joint, creating a cup-like appearance on one side and a pointed appearance resembling a pencil on the other side. This appearance is specific to arthritis mutilans.
24
Q
How is the management of Psoriatic Arthritis coordinated, and which professionals are involved?
A
The management involves coordination between dermatologists, rheumatologists, and a multidisciplinary team. Treatment may include NSAIDs, steroids, DMARDs (e.g., methotrexate, leflunomide, sulfasalazine), and anti-TNF medications (etanercept, infliximab, adalimumab), as well as Ustekinumab, a monoclonal antibody targeting interleukin 12 and 23.
25
What is the characteristic feature of ankylosing spondylitis in the axial skeleton?
Ankylosing spondylitis is characterized by partial or complete fusion and rigidity of the spine, leading to a chronic inflammatory disease of the axial skeleton.
26
What is the genetic predisposition associated with ankylosing spondylitis, and how common is it?
Ankylosing spondylitis has a genetic predisposition, with 90% of cases associated with HLA B27. There is often a strong family history of the condition.
27
What is the typical age of onset for ankylosing spondylitis?
The typical age of onset for ankylosing spondylitis is 20-40 years.
28
What are the clinical features related to articular symptoms in ankylosing spondylitis?
Articular symptoms include inflammatory spinal and back pain, with a gradual onset of dull pain that progresses slowly. Early morning stiffness lasting more than 30 minutes that improves with activity is a common feature. Peripheral arthritis, though rare, may also occur in joints like the knee, shoulders, and hips.
29
What are the signs associated with the lumbar spine in ankylosing spondylitis?
Patients with ankylosing spondylitis often display restricted movements in the lumbar spine. Schobers test is used to measure lumbar spine flexion, involving measurements below and above the posterior superior iliac crests while the patient bends forward. Normal extension should exceed 20cm.
30
How does ankylosing spondylitis manifest in the thoracic spine?
In the thoracic spine, dorsal kyphosis can develop as the disease progresses. Some cases exhibit reduced chest expansion, defined as less than 5 cm.
31
What are the manifestations of ankylosing spondylitis in the cervical spine?
Movements at the cervical spine can be globally reduced, with the neck forced into a flexed position by dorsal kyphosis. The occiput-to-wall distance is measured with the patient standing against a wall, providing a readout of fixed neck flexion (normal = 0).
32
What signs indicate tenderness in ankylosing spondylitis?
Tenderness in ankylosing spondylitis is observed in the sacroiliac joints and may include inflammatory enthesitis, such as the Achilles tendon and iliac crests, which is painful on palpation.
33
Describe the characteristic posture seen in late ankylosing spondylitis.
Late-stage ankylosing spondylitis is characterized by the loss of lumbar kyphosis with pronounced cervical lordosis, resulting in a 'question mark' posture.
34
How is the Schobers test used to assess ankylosing spondylitis?
The Schobers test is used to measure lumbar spine flexion in ankylosing spondylitis. It involves measuring 5cm below and 10cm above the posterior superior iliac crests while the patient is upright. The patient then bends forward, and the distance is remeasured. In normal situations, the extension should exceed 20cm.
35
What is the significance of the occiput-to-wall distance in ankylosing spondylitis assessment?
The occiput-to-wall distance is measured to assess ankylosing spondylitis. It provides a readout of fixed neck flexion, with a normal distance being 0.
36
What is the characteristic appearance on x-rays for ankylosing spondylitis?
X-rays of ankylosing spondylitis reveal characteristic features such as periostitis (inflammation of the periosteum), ankylosis (fusion of bones at the joint), osteolysis (bone destruction), and the "bamboo spine" appearance due to syndesmophyte formation.
37
How is the management of ankylosing spondylitis coordinated, and what are the potential treatment options?
Management involves coordination between healthcare professionals. Treatment options may include NSAIDs, physiotherapy, and, in severe cases, biologics such as TNF inhibitors. A multidisciplinary approach is essential for optimal care.
38
What is Ankylosing Spondylitis (AS), and what parts of the body does it primarily affect?
Ankylosing Spondylitis is an inflammatory condition affecting the axial skeleton, mainly the spine and sacroiliac joints, causing progressive stiffness and pain. It is also referred to as axial spondyloarthritis.
39
What is the strong genetic link associated with Ankylosing Spondylitis, and how common is it?
Ankylosing Spondylitis has a strong link with the HLA-B27 gene, present in around 90% of AS patients. However, it is estimated that less than 10% of people with the gene will develop AS. The condition is more common in men, although women can also be affected.
40
Describe the typical presentation of Ankylosing Spondylitis in terms of age, gender, and symptoms.
The typical presentation is a young adult male in their 20s, with symptoms developing gradually over at least three months. The main presenting features include pain and stiffness in the lower back and sacroiliac pain in the buttock region.
41
How do symptoms of Ankylosing Spondylitis vary with rest and activity?
Symptoms of Ankylosing Spondylitis worsen with rest, including increased pain and stiffness. Conversely, symptoms improve with movement and activity. The pain and stiffness are typically worse at night and in the morning, taking at least 30 minutes to improve in the morning.
42
What additional symptoms and problems can be associated with Ankylosing Spondylitis?
Additional symptoms and problems associated with Ankylosing Spondylitis include chest pain related to costovertebral and sternocostal joints, enthesitis (inflammation where tendons or ligaments insert into bone), dactylitis (inflammation of the entire finger), vertebral fractures, and shortness of breath related to restricted chest wall movement.
43
What are the key associations with Ankylosing Spondylitis, as remembered by the "5 As" mnemonic?
The key associations with Ankylosing Spondylitis can be remembered using the "5 As" mnemonic: Anterior uveitis, Aortic regurgitation, Atrioventricular block (heart block), Apical lung fibrosis (fibrosis of the upper lobes of the lungs), and Anemia of chronic disease.
44
What is the purpose of Schober’s Test, and how is it performed?
Schober’s test assesses spinal mobility. The patient stands straight, and the L5 vertebra is located. Points are marked 10cm above and 5cm below this level. The patient bends forward, and the distance between the points is measured. A length of less than 20cm indicates restricted lumbar movement, supporting a diagnosis of ankylosing spondylitis.
45
What are the key investigations for ankylosing spondylitis, and what information do they provide?
Key investigations include inflammatory markers (CRP and ESR), HLA B27 genetic testing, X-ray of the spine and sacrum, and MRI of the spine showing bone marrow edema early in the disease. Inflammatory markers may rise with disease activity, and X-rays can reveal characteristic features such as a "bamboo spine" and other changes.
46
What is the typical x-ray finding in the later stages of ankylosing spondylitis?
In the later stages of ankylosing spondylitis, a "bamboo spine" is a typical x-ray finding, indicating fusion of the sacroiliac and spinal joints. X-rays can also show squaring of vertebral bodies, subchondral sclerosis and erosions, syndesmophytes, ossification of ligaments, discs, and joints, as well as fusion of facet, sacroiliac, and costovertebral joints.
47
How is medical management approached for ankylosing spondylitis, and what are the first-line options?
Medical management involves controlling symptoms and preserving function. First-line options include non-steroidal anti-inflammatory drugs (NSAIDs). Second-line options are anti-TNF medications (e.g., adalimumab, etanercept, or infliximab). Third-line options include secukinumab or ixekizumab (monoclonal antibodies against interleukin-17) and upadacitinib (JAK inhibitor).
48
What additional management strategies are recommended for ankylosing spondylitis?
Additional management includes physiotherapy, exercise, and mobilization. Avoiding smoking is advised. Bisphosphonates are recommended for osteoporosis. Intra-articular steroid injections may be considered for specific joints. Severe joint deformity may require surgery, and the rheumatology multidisciplinary team is involved in overall patient management.
49
What is the defining characteristic of Reiter's syndrome, and what is its triad?
Reiter's syndrome is an infection-induced systemic illness characterized by an inflammatory synovitis. The triad includes urethritis, conjunctivitis/uveitis/iritis, and arthritis.
50
What are the most common preceding infections associated with Reiter's syndrome?
The most common preceding infections are urogenital, such as chlamydia and neisseria, and enterogenic, including salmonella and campylobacter.
51
What is the age range and sex distribution commonly observed in Reiter's syndrome?
Reiter's syndrome commonly presents in early adulthood, between the ages of 20 and 40, with an equal sex distribution.
52
What is the role of HLA B27 in Reiter's syndrome?
Reiter's syndrome is associated with HLA B27 positivity.
53
How does Reiter's syndrome manifest in response to an infection?
Reiter's syndrome occurs in response to an infection in another part of the body. Large joints, such as the knee, become inflamed around 1-3 weeks following the infection, triggering an autoimmune arthropathy.
54
What are the common symptoms of Reiter's syndrome, particularly related to arthritis?
Common symptoms include peripheral arthritis, typically asymmetrical oligoarthritis, starting 1-4 weeks after infection. Large joints of the lower limbs are most commonly affected. Axial arthritis, especially of the sacroiliac joints and lumbosacral spine, may occur in up to 40% of patients and is associated with HLA-B27.
55
What constitutional symptoms may be observed in Reiter's syndrome, and why is sepsis a concern?
Constitutional symptoms include fever, fatigue, and malaise, which can be severe and mimic sepsis (which needs to be excluded).
56
What signs are associated with Reiter's syndrome, apart from arthritis?
Signs include dactylitis, mucocutaneous lesions (keratodermia blenorrhagica, circinate balanitis, painless oral ulcers, hyperkeratotic nails), ocular lesions (conjunctivitis, iritis, anterior uveitis), and visceral manifestations (mild renal disease, carditis).
57
Describe the triad that defines Reiter's syndrome.
Reiter's syndrome is characterized by the triad of urethritis, conjunctivitis/uveitis/iritis, and arthritis.
58
What is the role of Enthesitis in Reiter's syndrome, and how does it manifest?
Enthesitis in Reiter's syndrome can manifest as Achilles tendonitis or plantar fasciitis.
59
What blood tests are recommended for investigating Reiter's syndrome, and what are the potential findings?
Recommended blood tests include inflammatory markers (raised), FBC, U+Es, LFTs, and HLA B27 (rarely necessary). Potential findings may include elevated inflammatory markers, abnormalities in FBC, U+Es, and LFTs. HLA B27 may or may not be positive.
60
What cultures should be obtained as part of the investigations for Reiter's syndrome?
Cultures of blood, urine, and stool should be obtained as part of the investigations for Reiter's syndrome.
61
Why is joint fluid analysis performed in Reiter's syndrome, and what is expected from the aspirate?
Joint fluid analysis is performed to rule out infection. The aspirate should be negative for infection in Reiter's syndrome.
62
What imaging studies are recommended for evaluating Reiter's syndrome?
X-rays of affected joints are recommended for evaluating Reiter's syndrome.
63
Why is ophthalmology opinion sought in the management of Reiter's syndrome?
Ophthalmology opinion is sought in the management of Reiter's syndrome to address ocular manifestations, including conjunctivitis, iritis, and anterior uveitis.
64
How is the management of Reiter's syndrome approached, and what are the primary treatment goals?
Management is aimed at the underlying infectious cause (e.g., genitourinary infection) and symptomatic relief. NSAIDs are commonly used, and severe cases may require intra-articular or intramuscular steroid injections. Primary treatment goals include addressing the infection and providing relief from symptoms.
65
What is the typical prognosis for Reiter's syndrome, and how often do relapses occur?
Most cases of Reiter's syndrome are self-limiting, with 90% resolving spontaneously within 6 months. Relapses occur in around 30-50% of cases, often due to re-exposure to an infective agent.
66
In what cases might chronic progressive erosive disease develop in Reiter's syndrome, and what treatment is recommended?
Chronic progressive erosive disease may develop in around 10% of cases, particularly when there is persistence of the disease and positivity to HLA-B27. DMARDs are recommended in such cases for long-term management.
67
What is the role of NSAIDs in the management of Reiter's syndrome?
NSAIDs play a key role in the symptomatic relief of Reiter's syndrome.
68
How is the persistence of Reiter's syndrome associated with HLA-B27 positivity addressed in treatment?
The persistence of Reiter's syndrome and HLA-B27 positivity may warrant the use of DMARDs (Disease-Modifying Anti-Rheumatic Drugs) for long-term management.
69
What is the primary characteristic of reactive arthritis, and how does it typically manifest in the joints?
Reactive arthritis involves synovitis in one or more joints in response to an infective trigger. It typically causes acute monoarthritis, affecting a single joint, most commonly the knee, presenting with a warm, swollen, and painful joint.
70
How does reactive arthritis differ from septic arthritis, and what is a key distinguishing feature?
Reactive arthritis differs from septic arthritis in that patients with reactive arthritis do not have an infection inside the joint. Septic arthritis involves joint infection. The absence of joint infection is a key distinguishing feature between reactive arthritis and septic arthritis.
71
What are the most common triggers for reactive arthritis, and which sexually transmitted infection may cause it?
The most common triggers for reactive arthritis are gastroenteritis and sexually transmitted infections. Chlamydia is a sexually transmitted infection that may cause reactive arthritis. Gonorrhoea, on the other hand, typically causes septic arthritis rather than reactive arthritis.
72
What is the association between reactive arthritis and the HLA B27 gene?
Reactive arthritis is a seronegative spondyloarthropathy, and there is an association with the HLA B27 gene.
73
In patients with reactive arthritis, what condition needs to be excluded, and why is HIV testing recommended?
In patients with reactive arthritis, septic arthritis needs to be excluded. HIV testing is recommended as reactive arthritis is more common in patients with HIV, and HIV needs to be excluded in these cases.
74
What are the associations often observed in reactive arthritis, and how are they remembered using a mnemonic?
Associations in reactive arthritis include bilateral conjunctivitis (non-infective), anterior uveitis, urethritis (non-gonococcal), and circinate balanitis (dermatitis of the head of the penis). They are remembered with the mnemonic "can't see, pee, or climb a tree."
75
What is the recommended approach for managing patients with an acute warm, swollen, and painful joint?
Patients with an acute warm, swollen, and painful joint should be treated according to the local hot joint policy. Septic arthritis needs to be excluded, and antibiotics may be given until septic arthritis is ruled out. Joint aspiration is required for synovial fluid analysis.
76
What does the management of reactive arthritis involve after septic arthritis is excluded?
After septic arthritis is excluded, the management of reactive arthritis involves treating the triggering infection (e.g., chlamydia), using NSAIDs, administering steroid injections into affected joints, and considering systemic steroids, particularly if multiple joints are affected.
77
What is the typical resolution timeframe for most cases of reactive arthritis, and how are recurrent cases managed?
Most cases of reactive arthritis resolve within 6 months and do not recur. Recurrent cases may require DMARDs (Disease-Modifying Anti-Rheumatic Drugs) or anti-TNF medications for long-term management.
78
What is the medical term for inflammation of the joint space caused by infection?
Septic arthritis
79
What is the most common causative organism of septic arthritis in adults?
Staphylococcus aureus is the most common cause of septic arthritis in adults.
80
Which organisms are the second most common cause of septic arthritis?
Streptococci are the second most common causative organisms in septic arthritis.
81
In children, what organism was historically the most common cause of septic arthritis, and what has changed this?
Haemophilus influenzae was historically the most common cause in children, but its incidence has decreased in areas where Haemophilus vaccination is practiced.
82
What organism is associated with septic arthritis in young adults, and how common is it in Western Europe?
Neisseria gonorrhoea is associated with septic arthritis in young adults, but it is now thought to be rare in Western Europe.
83
Which population is Escherichia coli commonly associated with in septic arthritis?
Escherichia coli is commonly associated with septic arthritis in the elderly, intravenous drug users, and the seriously ill.
84
What is the most common mode of spread for septic arthritis, and what are the other modes mentioned?
The most common mode of spread for septic arthritis is hematogenous spread. It can also be an extension of local infection.
85
Why is septic arthritis considered an orthopaedic emergency?
Septic arthritis is considered an orthopaedic emergency due to rapid irreversible damage to hyaline articular cartilage.
86
How does septic arthritis typically present in terms of joint involvement and symptoms?
Septic arthritis typically presents as an acute monoarthropathy, affecting a single joint with symptoms of a warm, red, and painful joint. Any joint that is hot, red, and tender is considered a septic joint until proven otherwise, and joint aspiration is crucial for confirmation. The knee is the most commonly affected joint.
87
What signs may be observed in a patient with septic arthritis?
Signs of septic arthritis may include reduced range of motion (ROM), swelling, and systemic fever.
88
What blood tests are recommended for investigating septic arthritis, and what may be found in the blood?
Recommended blood tests include CRP (C-reactive protein), and if pyrexial, blood culture (positive in 30-60% of cases). Elevated CRP may be found in the blood.
89
What is the significance of joint fluid aspiration in septic arthritis, and what should be excluded during analysis?
Joint fluid aspiration is crucial for confirming septic arthritis. It involves microscopy, culture, sensitivity testing, and exclusion of crystals, such as those seen in gout.
90
How is septic arthritis managed in terms of antibiotics, and what antibiotics are initially recommended?
Empirical antibiotics are avoided if the patient is not septic. If septic, flucloxacillin is recommended, and if under 5 years old, ceftriaxone is added for Haemophilus influenzae cover. Adjustments are made based on confirmed organisms.
91
What is the general approach to antibiotic treatment once the culture results are available in septic arthritis?
Once culture results are available, 1-2 weeks of IV antibiotics specific to the cultured organism are administered. Joint washout may be required, and if good progress is observed, PO antibiotics are continued until a total of 6 weeks of antibiotics is completed.
92
How is the response to treatment evaluated in septic arthritis?
Response to treatment in septic arthritis is based on clinical findings and serial CRP (C-reactive protein) levels.
93
What does the term "septic arthritis" refer to?
Septic arthritis refers to an infection inside a joint.
94
In what age group is septic arthritis most common?
Septic arthritis can occur at any age but is most common in children under 4 years.
95
Why is septic arthritis considered an emergency?
Septic arthritis is considered an emergency because the infection can quickly destroy the joint and cause serious systemic illness, with a mortality rate around 10%. Early recognition and management are essential.
96
What is the mortality rate associated with septic arthritis?
Septic arthritis has a mortality rate around 10%.
97
Which joints are most commonly affected by septic arthritis?
Septic arthritis usually affects a single joint, often the knee or hip.
98
What are the typical symptoms of septic arthritis?
Typical symptoms of septic arthritis include a hot, red, swollen, and painful joint, refusal to weight bear, stiffness, reduced range of motion, and systemic symptoms such as fever, lethargy, and sepsis.
99
What is the most common causative organism of septic arthritis?
Staphylococcus aureus is the most common causative organism of septic arthritis.
100
In sexually active teenagers, what bacterium may cause septic arthritis?
In sexually active teenagers, Neisseria gonorrhoea (gonococcus) may cause septic arthritis.
101
Which bacteria can be causative organisms in septic arthritis apart from Staphylococcus aureus and Neisseria gonorrhoea?
Other bacteria include Group A streptococcus (Streptococcus pyogenes), Haemophilus influenza, and Escherichia coli (E. coli).
102
What is the differential diagnosis for septic arthritis?
The differential diagnosis for septic arthritis includes transient synovitis, Perthes disease, slipped upper femoral epiphysis, and juvenile idiopathic arthritis.
103
What is the recommended management for a patient with suspected septic arthritis?
Patients with suspected septic arthritis require admission to the hospital, involvement of the orthopaedic team, joint aspiration, and empirical IV antibiotics until microbial sensitivities are known. Antibiotics are usually continued for 3 to 6 weeks.
104
Why is joint fluid aspiration essential in the management of septic arthritis?
Joint fluid aspiration is essential in the management of septic arthritis as it helps exclude or confirm the diagnosis. The sample is sent for gram staining, crystal microscopy, culture, and antibiotic sensitivities.
105
What is the significance of a purulent joint fluid in septic arthritis?
In septic arthritis, the joint fluid may be purulent, indicating the presence of pus.
106
How long are antibiotics typically continued when septic arthritis is confirmed?
Antibiotics are usually continued for 3 to 6 weeks in total when septic arthritis is confirmed.
107
In severe cases of septic arthritis, what additional intervention may be required?
In severe cases of septic arthritis, surgical drainage and washout of the joint may be required to clear the infection.
108
What are the common symptoms Maurice is experiencing?
Maurice is experiencing gradually progressive low back pain and stiffness. The pain wakes him up several times at night, and the stiffness tends to be worse when he wakes up, improving as he moves.
109
What findings are observed in Maurice's examination?
Maurice's examination shows mild deformity of the spine and hip, as well as tenderness over the buttock.
110
What radiographic findings are seen in Maurice's case?
X-rays in Maurice's case show erosion of the sacroiliac joint.
111
What symptoms does Clint present with?
Clint presents with a red, warm, and swollen left knee, experiencing significant pain that hinders his ability to walk. He also mentions that symptoms started a few days ago after tripping and cutting his knee.
112
What is Clint's body temperature, and what does it indicate?
Clint's body temperature is 38 degrees Celsius or 100.4 degrees Fahrenheit, indicating fever, which suggests systemic involvement and inflammation.
113
What diagnostic procedure is performed in Clint's case, and what does it reveal?
In Clint's case, an arthrocentesis is performed, revealing that synovial fluid is purulent.
114
How are seronegative spondyloarthropathies characterized, and what is the significance of HLA-B27?
Seronegative spondyloarthropathies are characterized by the absence of both rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (anti-CCP). HLA-B27 has a strong association with seronegative spondyloarthropathies.
115
What are the subtypes of seronegative spondyloarthropathies, and how can they be remembered?
The subtypes of seronegative spondyloarthropathies are remembered by the mnemonic PAIR: P for Psoriatic arthritis, A for Ankylosing spondylitis, I for Inflammatory bowel disease-associated arthritis, and R for Reactive arthritis.
116
In which joint does Clint experience symptoms, and what is performed to assess the joint?
Clint experiences symptoms in his left knee. To assess the joint, an arthrocentesis is performed, which involves extracting and analyzing synovial fluid from the joint.
117
What radiographic findings are seen in Maurice's case, and where does the erosion occur?
X-rays in Maurice's case show erosion of the sacroiliac joint. The erosion occurs in the sacroiliac joint, indicating pathology in the connection between the sacrum and ilium.
118
Why is Clint's condition considered an emergency?
Clint's condition is considered an emergency because septic arthritis involves infection inside the joint, which can quickly destroy the joint and lead to serious systemic illness. Early recognition and management are essential.
119
What is the significance of synovial fluid being purulent in Clint's case?
The purulent synovial fluid in Clint's case indicates the presence of pus, suggesting an infectious etiology. This finding is crucial for diagnosing septic arthritis, and it prompts the need for immediate management to prevent joint destruction.
120
What is psoriatic arthritis, and what is its association with psoriasis?
Psoriatic arthritis is an autoimmune disease characterized by joint inflammation, often occurring in individuals with psoriasis or a family history of psoriasis. Psoriasis, an autoimmune skin condition, leads to the formation of psoriatic plaques, and in some cases, T cells involved in psoriasis may also affect the joints, triggering psoriatic arthritis.
121
What triggers the immune system in psoriasis, leading to joint inflammation in psoriatic arthritis?
In psoriasis, skin self-antigens are seen as foreign, leading to T cells releasing cytokines such as TNF, IL-12, and IL-23. These cytokines recruit and activate other immune cells, triggering keratinocytes and fibroblasts to proliferate. Psoriatic plaques, characterized by red, raised patches with silvery scales, are formed due to the proliferation of keratinocytes and fibroblasts. In some individuals with psoriasis, T cells may also affect the joints, leading to joint erosion and ossification, causing psoriatic arthritis.
122
What are the symptoms of psoriatic arthritis, and how does it relate to psoriatic plaques?
Symptoms of psoriatic arthritis include pain, swelling, and stiffness of the affected joints. Psoriatic plaques usually precede arthritis, but arthritis can sometimes precede them. Less than 30% of individuals with psoriasis develop psoriatic arthritis.
123
What are the types of psoriatic arthritis, and what joints do they affect?
Psoriatic arthritis has several types, and the most common is the distal interphalangeal predominant type, affecting joints nearest to the ends of the fingers and toes. It may lead to dactylitis (inflammation of the fingers) and nail abnormalities. Severe cases may progress to arthritis mutilans, characterized by extensive bone erosion resulting in a telescopic digit appearance or "opera-glass hand."
124
How is psoriatic arthritis diagnosed, and what characteristic radiographic sign may be seen?
Diagnosis involves an X-ray, which may show joint erosion and osteopenia. A characteristic radiographic sign is the pencil-in-cup appearance, resulting from periarticular erosions and bone resorption, making the joint look slimmer than the surrounding soft tissue.
125
What is the treatment approach for psoriatic arthritis, and what are the options for more severe cases?
Treatment for mild cases includes NSAIDs. Non-biologic DMARDs, especially leflunomide, can be used for more severe cases. If NSAIDs and non-biologic DMARDs are ineffective, biologic DMARDs like TNF inhibitors can be used to halt disease progression. In rare cases, surgery may be performed to repair damaged joints.
126
What is ankylosing spondylitis, and who is most commonly affected by this condition?
Ankylosing spondylitis is a chronic spondyloarthropathy that often affects young and middle-aged males. The exact cause is unknown, but an underlying autoimmune reaction, where T cells mistake type I and type II collagen in the joints as foreign, is one theory.
127
Which regions of the body are typically affected by ankylosing spondylitis, and what joints are involved?
Ankylosing spondylitis typically affects the spine, causing inflammation of the intervertebral and facet joints. It can also affect sacroiliac joints between the sacrum and hip bones and joints in the cervical and thoracic regions. Destruction of articular cartilage leads to fibroblast activation, fibrin deposition, limited joint motion due to fibrous bands, and eventual ossification with the formation of syndesmophytes.
128
What is the role of fibroblasts in ankylosing spondylitis, and how does ossification occur in affected joints?
In ankylosing spondylitis, fibroblasts are activated due to destruction of articular cartilage. They replace destroyed joints with fibrin, forming a tough fibrous band around the joints, limiting their range of motion. Ossification occurs when fibrous tissue at the joint edges turns into small bony outgrowths called syndesmophytes.
129
What joints are commonly affected in the spine in ankylosing spondylitis?
Ankylosing spondylitis characteristically affects the intervertebral joints and facet joints in the spine.
130
How is ankylosing spondylitis typically diagnosed, and what radiographic sign may be seen?
An X-ray is commonly used for the diagnosis of ankylosing spondylitis, and a radiographic sign that may be observed is the bamboo spine, which is characterized by syndesmophytes leading to a fused appearance of the vertebrae, resembling a bamboo stalk.
131
What is the general treatment approach for ankylosing spondylitis, and what interventions may be considered?
Treatment for ankylosing spondylitis aims to manage symptoms and preserve function. NSAIDs are commonly used for pain and inflammation. For more severe cases, anti-TNF medications and other third-line options like Secukinumab or Ixekizumab may be considered. Intra-articular steroid injections may be used for specific joints. Additional management includes physiotherapy, exercise, smoking cessation, bisphosphonates for osteoporosis, and, in severe cases, surgery for severe joint deformity.
132
What are the articular symptoms associated with ankylosing spondylitis, and how does it affect the spine?
Ankylosing spondylitis causes articular symptoms such as morning stiffness, lower back pain that worsens at night, lasts for more than 30 minutes, and improves with movement and exercise. The condition can lead to kyphotic deformity, limited range of motion in the spine due to fibrin deposition and syndesmophytes, and potential immobility of the affected part of the spine. Pain and tenderness can occur in the sacroiliac joints, leading to lower back or buttock pain. The cervical or thoracic region's involvement may cause neck or chest wall pain and stiffness.
133
What extra-articular symptoms may be associated with ankylosing spondylitis, and how does it affect breathing?
Ankylosing spondylitis may present with extra-articular symptoms like weight loss, fever, fatigue, uveitis, tendonitis, and shortness of breath. The condition can cause spine stiffness leading to impaired chest expansion, contributing to breathing difficulties. Additionally, ankylosing spondylitis can result in restrictive lung disease and pulmonary fibrosis in the apical parts of the lungs. In the heart, it may cause aortitis, leading to aortic wall inflammation and aortic insufficiency.
134
How is ankylosing spondylitis diagnosed, and what are the characteristic findings in diagnostic imaging?
Ankylosing spondylitis is diagnosed based on imaging studies such as X-rays, CT scans, or MRIs, which can reveal joint space erosion and narrowing. The characteristic bamboo spine appearance may be observed, resulting from ossification of the annulus fibrosus on the outside of a straightened spine. Genetic testing for HLA-B27 can also confirm the diagnosis.
135
What is the treatment approach for inflammation and pain in ankylosing spondylitis, and what monitoring is needed?
Inflammation and pain in ankylosing spondylitis are typically treated with NSAIDs like ibuprofen. Exercise and physical therapy can also help alleviate pain and improve mobility. Individuals with ankylosing spondylitis require frequent monitoring of chest expansion. In more severe cases, DMARDs (disease-modifying antirheumatic drugs) such as sulfasalazine and methotrexate may be prescribed to control symptoms and slow disease progression.
136
What is inflammatory bowel disease (IBD), and how can it be associated with seronegative arthritis?
Inflammatory bowel disease (IBD) is characterized by chronic inflammation in the gastrointestinal tract, accompanied by systemic symptoms like fatigue, fever, and unintentional weight loss. Seronegative arthritis may be secondary to IBD, occurring in individuals with Crohn's disease or ulcerative colitis. IBD-associated arthritis often affects the knee or spine and is suspected when joint or back pain and stiffness accompany gastrointestinal symptoms. Diagnosis involves endoscopy or colonoscopy with biopsy. Treatment includes a step-up approach with anti-inflammatory medications.
137
What is reactive arthritis, and what microorganisms are commonly associated with its development?
Reactive arthritis, previously known as Reiter's syndrome, is an autoimmune condition that typically follows a bacterial infection of the gastrointestinal or urinary tract. Commonly associated microorganisms include Shigella, Yersinia, Chlamydia, Campylobacter, and Salmonella. These gram-negative bacteria have lipopolysaccharides (endotoxins) on their surface, leading to a strong immune response. The development of reactive arthritis is unclear but may involve endotoxins reacting with MHC molecules on cell surfaces, making them appear foreign.
138
What is the classic triad of symptoms associated with reactive arthritis, and what is a mnemonic for identification?
The classic triad of symptoms in reactive arthritis includes arthritis, urethritis, and conjunctivitis. A helpful mnemonic for identification is "can't see, can't pee, can't climb a tree." Besides joint pain, other symptoms may involve the knee, ankles, hips, small joints in the feet, and multiple joints. Additionally, reactive arthritis can cause keratoderma blenorrhagicum on the soles and palms and cervicitis, leading to dyspareunia. The condition is diagnosed based on a history of previous infection, clinical examination, arthrocentesis, and genetic testing for HLA-B27.
139
How is reactive arthritis diagnosed, and what are common findings in arthrocentesis?
Reactive arthritis is diagnosed based on a history of previous infection, clinical examination, and findings in arthrocentesis. In arthrocentesis, synovial fluid is usually clear and sterile since the bacteria producing endotoxin do not invade the joints. Genetic testing for the HLA-B27 gene is often positive. Throat and genital swabs might be used to look for Chlamydia. In terms of treatment, NSAIDs like ibuprofen can be used for symptom relief, and corticosteroids may be given if NSAIDs are ineffective.
140
What is septic arthritis, and how does it differ from reactive arthritis?
Septic arthritis, or infectious arthritis, is joint inflammation caused by a microbe that invades the bones, causing damage. Unlike reactive arthritis, septic arthritis is not autoimmune. Bacteria can enter the joint through various means, including preexisting osteomyelitis, hematogenous spread, or direct inoculation. Two main types are gonococcal arthritis, caused by Neisseria gonorrhoeae, and non-gonococcal arthritis, involving pathogens like Staphylococcus aureus, Streptococcus species, Mycobacterium tuberculosis, and Borrelia species.
141
What is the pathophysiology of septic arthritis, and how does it affect the joint?
In septic arthritis, bacteria invade the synovial cavity, destroying articular cartilage with toxins and attracting inflammatory cells, including macrophages. Macrophages release cytokines, triggering an inflammatory response with increased blood and immune cell influx. Vascular permeability rises, leading to fluid leakage, increased intra-articular pressure, and necrosis of bones and cartilage. This damages the joint further. Inflammatory symptoms include redness, swelling, warmth, pain, limited mobility, and fever.
142
How does gonococcal arthritis differ from non-gonococcal arthritis in terms of joint involvement and severity?
Gonococcal arthritis typically affects multiple joints, accompanied by skin lesions and tenosynovitis. Non-gonococcal arthritis usually affects a single joint, often the knee, and tends to be more severe than gonococcal arthritis.
143
What are the diagnostic steps for septic arthritis, and what are the typical findings in arthrocentesis?
Diagnosis of septic arthritis involves arthrocentesis. Typical findings include purulent synovial fluid with a high white blood cell count (>50,000 cells/microliter), positive gram stain, and positive culture identifying the causative bacteria. Imaging (X-ray, ultrasound, CT scan, or MRI) can show bone erosion and joint effusions, especially for difficult-to-aspirate joints like the hip and sacroiliac. Blood tests may reveal inflammation with raised ESR, CRP, and leukocytosis.
144
What is the empirical treatment for suspected gonococcal infection in septic arthritis, and when can it be adjusted based on culture results?
Empirical treatment for suspected gonococcal infection in septic arthritis typically consists of ceftriaxone. Once culture results are available, the treatment can be adjusted based on the specific bacteria identified. If there are concerns about resistance or chlamydia co-infection, dual therapy with ceftriaxone and azithromycin may be administered. In addition to antibiotic therapy, joint aspiration and washout may be required, either through arthrocentesis or the surgical operation known as arthrotomy.
