Rheumatology II Flashcards

Question

Infection from which organisms typically causes reactive arthritis? [1]

Answer 1

The most common triggers of reactive arthritis are **gastroenteritis** or **sexually transmitted infections.** - **Chlamydia** may cause reactive arthritis. ## Footnote **NB**: Gonorrhoea typically causes septic arthritis rather than reactive arthritis.

Answer 2

**Blood tests** - ongoing inflammation (raised **ESR** and **CRP**) - **ANA and RF**: to rule out other forms of arthritis - **HLA B27** - present in 40% patients **Urine test:** - **NAAT** to detect **Chlamydia trachomatis** **Stool test:** - Test for **Salmonella, Shigella, Campylobacter, and Yersinia** **Radiological changes:** - Early stages - no specific changes - chronic ReA - radiographic changes in 70% **Synovial fluid analysis:** - to **exclude** alternative diagnoses like **septic arthritis**; **gout and pseudogout** - Synovial cultures are always negative. ## Footnote **NB** - Stool cultures are usually negative by the time arthritis occurs, but should be considered if diarrhoea present or recently resolved.

Answer 3

**Treatment of arthritis** - first-line therapy for acute phase: **NSAIDs** - **Corticosteroids**: during an acute flare, or unresponsive to NSAIDs. - **DMARDs**: **Sulfasalazine** is effective in peripheral disease and has little or no effect on spinal disease; **Methotrexate** is effective in treating both acute and chronic ReA especially, in patients with spinal involvement. - **Anti-TNF-α therapy:** **Etanercept** is an emerging therapy, **Antibiotics** for acute Chlaymdia infection - **doxycycline or azithromycin** ## Footnote **NB** - Antibiotics may be given until septic arthritis is excluded.

Answer 4

topical steroids.

Answer 5

Body produces **B cells**. Normally when they **react** to **self they get destroyed.** In SLE they **escape** from **peripheral circulation** - they **differentiate** into **plasma** **cells** and **produce** **antibodies** to **nuclear** parts of cells (thus ANA) **Complexes of antibody-antigen deposit** in the **body** and **cause** **damage** e.g. skin, joints and renal are most common When deposited the immune system causes complexes. But in SLE, have **complement** **dysfunction**. This **adds to the inflam cascade** and actives inflam cytokines Over the course of lifetime, get waxes and wanes of SLE

Answer 6

**Joint pain & swelling** (without joint destruction) **Malar rash** - spares nasolabial folds. Feels inflammed **Mouth ulcers** **Reynauds** **Livedo reticularis** - broken lattice work in inflam. disease **Photosensitivity** **Lupus nephritis** **Alopecia** **Discoid erythematosus** **Lymphadenopathy**

Answer 7

**ANA** - **DS-DNA** - highly specific to SLE, meaning a positive result suggests SLE rather than other causes. But only half have ds-ANA **Anti-SM** - highly specific but not very sensitive Anti-RNP Anti-Ro Anti-La

Answer 8

**Skin**: - **hydroxychloroquine** or azathriopine. **Joints** - hydroxychloroquine or methotrexate **Vital organs:** - Azathriopine - MMF - Cyclophosphamide - esp. if renal involvement **PassMed**: All patients - **hydroxychloroquine** **Mild Disease**: - hydroxychloroquine & low dose pred. - Methotrexate and NSAIDs can also be used **Moderate disease:** - hydroxychloroquine with short term pred. - Additional agents may include methotrexate, azathioprine, mycophenolate and ciclosporin. **Severe disease:** - induction therapy of intense immunosuppressants and then maintenence - DMARDs (methotrexate; MMF; cyclophoshamide) & Biologics (Rituximab; Belimumab) may also be used

Answer 9

**Sicca (dryness)** - eyes (keratoconjunctivitis sicca) - mouth - vagina **Arthralgia** **Raynaud's, myalgia** **Sensory polyneuropathy** **Gland swelling** (parotitis)

Answer 10

**Assess clinical features:** - **dry eyes** > 3 months; use of tear substitutes more than three times daily or presence of keratoconjunctivitis sicca with ocular staining score ≥3. - **dry mouth** consistently **Serology**: - anti-Ro; anti-La - Elevated IgG levels **Further tests:** - **Schirmer's test** - < 5 mm/5mins wetting and / or Rose Bengal scores of > 4 - **Sialometry** < 1.5ml/15mins **Histopathology** - Lip biopsy exhibiting focal lymphocytic sialadenitis with a focus score ≥1 per 4 mm² glandular tissue area.

Answer 11

* **anticardiolipin antibodies** * **anti-beta2 glycoprotein I (anti-beta2GPI) antibodies** * **lupus anticoagulant**

Answer 12

Renal - **lupus nephritis** **Pleuritis**; pneumonitis; PE **Pericarditis**; **Reynauds**; Atherosclerosis **Headache or migraine**; seizure; pyschosis

Answer 13

**anti-phospholipid syndrome** (20-30%), **Sjogren**'s disease (17.5%) and autoimmune **thyroid disease** (7.5%).

Answer 14

The European League Against Rheumatism (EULAR) / American College of Rheumatology (ACR) criteria (2019) can be used for diagnosis. This takes into account the clinical features and autoantibodies suggestive of SLE. **uses 11 criteria of which 4 or more are required for diagnosis**

Answer 15

**Nephritis**: - Lupus nephritis: can lead to proteinuira; haematuria; end stage kidney disease **CV disease**: - CAD; myocarditis; pericarditis; heart failure **Pulmonary**: - ILD; pulmonary HTN; acute lupus pneumonitis **Neuropsyc:** - Head and mood to stroke or seizures **Hematologic abnormalities**: - leukopenia, lymphopenia, thrombocytopenia and autoimmune hemolytic anaemia.

Answer 16

**anti-Smith**: highly specific (> 99%), sensitivity (30%)

Answer 17

Photosensitive lesions of the face Scarring alopecia Hyper & hypopigmentation

Answer 18

* **topical steroid cream** * oral **antimalarials** may be used second-line e.g. **hydroxychloroquine** * **avoid sun exposure**

Answer 19

Sjögren’s syndrome is an autoimmune condition where you get **lymphocytic infiltration of exocrine glands** notably the **lacrimal and salivary glands**, causing symptoms of **dry mouth, eyes and vagina**. Dry eyes and dry mouth can be called sicca symptoms.

Answer 20

Aberrant immune response - **autoreactive T cells become activated and infiltrate exocrine glands.** Within the affected glands, there is a marked increase in pro-inflammatory cytokines including interleukin-1 (IL-1), tumour necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ). The local inflammatory milieu results in glandular dysfunction through both direct cytotoxic effects on acinar epithelial cells and disruption of normal glandular architecture. **B cell hyperactivity** is another hallmark of Sjögren's syndrome. There is **increased production of autoantibodies such as anti-Ro/SSA and anti-La/SSB,** which are directed complexes within the nucleus of glandular epithelial cells. **These autoantibodies** may contribute to **tissue damage either directly or via immune complex formation and deposition within glandular tissues**. Chronic inflammation leads to **fibrosis and atrophy of the exocrine glands over time**. The resultant loss of functional **acinar cells impairs saliva and tear production**, manifesting clinically as dry mouth and dry eyes.

Answer 21

**Primary treatment options:** * **Artificial tears** (e.g., polyvinyl alcohol eye drops during the day and carbomer gel at night) * **Artificial saliva** * **Vaginal lubricants** * **Pilocarpine** (oral) can be used to stimulate tear and saliva production * **Hydroxychloroquine** may be considered, mainly in patients with associated joint pain **Secondary treatment options** are usually prescribed by an ophthalmologist and include: * **Topical NSAIDs or Corticosteroids**: usually short-term use. Associated with corneal complications long-term. * **Topical cyclosporin**: reserved for patients needing recurrent courses of topical steroid. * **Serum tear drops:** application of autologous or allogenic serum. Variable efficacy. ## Footnote **NB**: Pilocarpine stimulates muscarinic receptors, stimulating the parasympathetic nerves and promoting salivary and lacrimal gland secretion.

Answer 22

The major complication of SS is **lymphoma**.

Answer 23

**livedo racemosa** *permanent Livedo reticularis*

Answer 24

**Libmann-Sacks endocarditis** is a non-bacterial endocarditis with growths (vegetations) on the heart valves (most often the mitral and aortic valves). It is associated with SLE and antiphospholipid syndrome.

Answer 25

**primary thromboprophylaxis** - low-dose aspirin **secondary thromboprophylaxis** * initial venous thromboembolic events: **lifelong warfarin with a target INR of 2-3** * recurrent venous thromboembolic events: **lifelong warfarin**; if occurred whilst taking warfarin then consider **adding low-dose aspirin, increase target INR to 3-4** * **arterial thrombosis** should be treated with lifelong warfarin with **target INR 2-3**