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2 SLE cases

5K views 6 replies 3 participants last post by  1TA2B 
#1 · (Edited)
case 1

A 44-year-old woman presents to the physician for her annual health maintenance examination. She states that she is feeling somewhat more lethargic and fatigued than usual. These symptoms began 3 months ago and have been progressing. She has a 15-year history of systemic lupus erythematosus (SLE). On examination, she is more pale than usual. A complete blood count reveals a hemoglobin of 9.1 g/dL. A peripheral blood smear is most likely to demonstrate what?

Answer Choices
A. Acanthocytes
B. Discocytes
C. Schistocytes
D. Spherocytes
E. Target cells

case 2

A 27-year-old woman presents to the physician because of joint pain, fatigue, weight loss, and symmetrical rash on both cheeks. She states that the joint pain is largely confined to her hands, but can occasionally involve her wrists. The laboratory investigation is positive for antinuclear antibody. A radiograph of the hand is most likely to reveal what abnormality?

Answer Choices
A. Erosions in the ulnar styloid
B. Expanded bony cortex
C. Osteophytes
D. Periarticular soft tissue swelling
E. Subchondral sclerosis
 
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#3 ·
SLE arthropathy!

Unlike rheumatoid arthritis, lupus arthritis is less disabling and usually does not cause severe destruction of the joints. Option A-unlikely.

Not osteophyte, subchondral sclerosis are typical of OA.

So must be -soft tissue swelling (which is common in RA, can also be the case in SLE) or expanded bony cortes (which is so non-specific)

So I would go with soft tissue swelling.

Looking forward to having the answer miss patho!

Thanks good one!
 
#5 ·
case 1

Option B (Discocytes) is correct. This patient has a long-standing history of SLE and has developed an anemia. The most likely cause based on the information provided is an anemia of chronic disease. Peripheral films most commonly show normochromic, biconcave erythrocytes that are also known as discocytes.

Option A (Acanthocytes) is incorrect. Acantocytes are also known as spur cells and are seen in patients with severe liver disease.

Option C (Schistocytes) is incorrect. Schistocytes are also known as fragmented cells and are the result of traumatic disruption of the membrane, such as the microangiopathic hemolytic anemias.

Option D (Spherocytes) is incorrect. Spherocytes are sometimes found in normal films; but when numerous, they are the result of hereditary spherocytosis, an autosomal-dominant condition.

Option E (Target cells) is incorrect. Target cells are seen in a variety of conditions ranging from iron deficiency anemia to thalassemias and liver disease.

High-yield Hit 1
Anemia of Chronic Disease

Figure 12-10 Hypochromic microcytic anemia of iron deficiency. Note the small RBCs containing a narrow rim of hemoglobin at the periphery. Contrast to the scattered, fully hemoglobinized cells derived from a recent blood transfusion given to the patient. (Courtesy of Dr. Robert W. McKenna, Department of Pathology, University of Texas Southwestern Medical School, Dallas.)
This is the most common form of anemia in hospitalized patients. It superficially resembles the anemia of iron deficiency, but it stems from inflammation-induced sequestration of iron within the cells of the reticuloendothelial system. It occurs in a variety of chronic inflammatory disorders, including the following:
Chronic microbial infections such as osteomyelitis, bacterial endocarditis, and lung abscess
Chronic immune disorders such as rheumatoid arthritis and regional enteritis
Neoplasms such as Hodgkin disease and carcinomas of the lung and breast

From Robbins Basic Pathology 7E by Kumar et al
High-yield Hit 2
The anemia of chronic disease is associated with low serum iron, and the RBCs may be normocytic and normochromic or hypochromic and microcytic, as in anemia of iron deficiency. However, the presence of increased storage iron in the marrow macrophages, a high serum ferritin level, and reduced total iron-binding capacity readily rule out iron deficiency as the cause of anemia. This combination of findings results from a block in the transfer of iron from the mononuclear phagocyte storage pool to the erythroid precursors. In addition, the compensatory increase in erythropoietin levels is not adequate for the degree of anemia. The teleologic explanation for iron sequestration in the presence of a wide variety of chronic inflammatory disorders is unclear; it may serve to inhibit the growth of iron-dependent microorganisms or to augment certain aspects of host immunity.
The common feature among the diverse diseases associated with the anemia of chronic disease is that all induce a prolonged state of systemic inflammation. The suppression of erythropoiesis and sequestration of iron in the storage compartment result from the action of a number of the inflammatory mediators, including interleukin 1 (IL-1), tumor necrosis factor (TNF), and interferon-α, which are secreted in response to the underlying chronic inflammatory or neoplastic disease. Administration of erythropoietin may improve the anemia, but only effective treatment of the underlying condition reliably corrects the anemia.

From Robbins Basic Pathology 7E by Kumar et al
High-yield Hit 3
Anemia of chronic disease
Chronic disorders are a common cause of anemia, being second only to iron-deficiency.
It may develop in patients with:
Non-organ specific autoimmune diseases (e.g., rheumatoid disease and SLE).
Chronic infective diseases (e.g., tuberculosis, malaria, and schistosomiasis).
Neoplasia: lymphoma and some carcinomas.
Blood film-Mainly normocytic and normochromic but a mild degree of microcytic, hypochromic anemia.
Laboratory findings are a reduced serum iron and reduced serum iron-binding capacity, with an increased or normal serum ferritin (cf. iron-deficiency anemia).
The disorder may be due to the failure of macrophages to transfer their iron stores to the bone marrow. Circulating red cells have a reduced life-span, and the marrow shows a lack of response to erythropoietin.
 
#6 ·
case 2

Option D (Periarticular soft tissue swelling) is correct. This patient has a characteristic malar rash, arthralgias, fatigue, and weight loss with a positive antinuclear antibody. The diagnosis of SLE is strongly suggested. The radiographic findings of SLE are somewhat variable, but almost always reveal periarticular soft tissue swelling. There can also be periarticular osteopenia.

Option A (Erosions in the ulnar styloid) is incorrect. This can be an early radiologic feature that is characteristic of rheumatoid arthritis. Erosions are absent in systemic lupus erythematosus (SLE).

Option B (Expanded bony cortex) is incorrect. An expanded bony cortex is seen in Paget disease, which it most commonly asymptomatic. It is caused by increased bone turnover caused by osteoclasts.

Option C (Osteophytes) is incorrect. Osteophytes are a common radiographic finding of osteoarthritis.

Option E (Subchondral sclerosis) is incorrect. This is a characteristic feature of osteoarthritis, which does not present with constitutional findings.

High-yield Hit 1
Table 80-2. Autoantibodies in Patients with Systemic Lupus Erythematosus (SLE)*
Test Sensitivity (%) Specificity (%) Predictive Value (%)
ANA 99 80 15-35
dsDNA 70 95 95
ssDNA 80 50 50
Histone 30-80 Moderate Moderate
Nucleoprotein 58 Moderate Moderate
Sm 25 99 97
RNP (U1-RNP) 50 87-94 46-85
Ro (SS-A) 25-35
La (SS-B) 15
PCNA 5 95 95

From Cecil Essentials of Medicine 6E by Andreoli et al
High-yield Hit 2
Various autoantibodies are found in patients with SLE and are the hallmark laboratory features of the disease (Table 80-2). Virtually all patients with SLE (99%) test positive for antinuclear antibodies when a sensitive assay is used. Although many of the specific antigens to which these antinuclear antibodies are directed have been determined, and are useful both diagnostically and clinically in SLE, some antibodies are also seen in other autoimmune diseases. Antibodies to double-stranded DNA and the Smith (Sm) antigen are highly specific for lupus, whereas antibodies to Ro and La antigens are also commonly found in patients with rheumatoid arthritis and are especially common in patients with Sjögren's syndrome. Certain antibodies are associated with specific clinical manifestations of disease. For example, many patients with lupus nephritis have anti-double-stranded DNA antibodies. The relationship between antibodies to ribosomal P or neuronal antigens and lupus cerebritis is still under investigation. Autoantibodies alone are not diagnostic for any autoimmune disease but must be interpreted in the clinical context.
SLE is a clinical diagnosis; no one test or feature is fully diagnostic of the disease. Furthermore, many patients' clinical syndromes "evolve" over time, and only after several years are they recognized as having SLE. To classify patients with SLE more accurately and reproducibly for research purposes, an internationally accepted set of diagnostic criteria was developed (Table 80-3). By design, the diagnostic specificity of these criteria is high, to ensure that all subjects enrolled in research studies truly have SLE. However, although these criteria are valuable for practicing clinicians, patients may have clinical lupus without meeting the criteria. More than half of the manifestations listed in Table 80-1 are not part of the criteria.

From Cecil Essentials of Medicine 6E by Andreoli et al
High-yield Hit 3
Table 80-3. Criteria for Classification of Systemic Lupus Erythematosus*
Criterion Definition
1. Malar rash Fixed erythema, flat or raised, over the malar eminences, tending to spare the nasolabial folds
2. Discoid rash Erythematous raised patches with adherent keratotic scaling and follicular plugging; atrophic scarring may occur in older lesions
3. Photosensitivity Skin rash as a result of unusual reaction to sunlight by patient history or physician observation
4. Oral ulcers Oral or nasopharyngeal ulceration, usually painless, observed by a physician
5. Arthritis Nonerosive arthritis involving two or more peripheral joints, characterized by tenderness, swelling, or effusion
6. Serositis a. Pleuritis: convincing history of pleuritic pain or rub heard by a physician or evidence of pleural effusion
OR
b. Pericarditis: documented by electrocardiogram or rub or evidence of pericardial effusion
7. Renal disorder a. Persistent proteinuria >0.5 g/day or >3+if quantitation not performed
OR
b. Cellular casts: may be red cell, hemoglobin, granular, tubular, or mixed
8. Neurologic disorder a. Seizures: in the absence of offending drugs or known metabolic derangements (e.g., uremia, ketoacidosis, or electrolyte imbalance)
OR
b. Psychosis: in the absence of offending drugs or known metabolic derangements (e.g., uremia, ketoacidosis, or electrolyte imbalance)
9. Hematologic disorder a. Hemolytic anemia: with reticulocytosis
OR
b. Leukopenia: <4000/mm3 total on two or more occasions
OR
c. Lymphopenia: <1500/mm3 on two or more occasions
OR
d. Thrombocytopenia: <100,000/mm3 in the absence of offending drugs
10. Immunologic disorder a. Anti-DNA: antibody to native DNA in abnormal titer
OR
b. Anti-Sm: presence of antibody to Sm nuclear antigen
OR
c. Positive finding of antiphospholipid antibodies based on (1) an abnormal serum level of IgG or IgM anticardiolipin antibodies, (2) a positive test result for lupus anticoagulant using a standard method, or (3) a false-positive serologic test for syphilis known to be positive for at least 6 months and confirmed by Treponema pallidum immobilization or fluorescent treponemal antibody absorption test
11. Antinuclear antibody An abnormal titer of antinuclear antibody by immunofluorescence or an equivalent assay at any point in time and in the absence of drugs known to be associated with "drug-induced lupus" syndrome
 
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