Lupus Site - a guide for lupus patients and their families

Lupus is a difficult disease to diagnose, & can be overlooked, often for years, unless the GP or consultant is alert to it's possibilities.

---

How do doctors know if you’ve got Lupus?

---

• Your medical history - what you tell the doctor
• What they find when we examine you
• What the blood tests show

To help distinguish Lupus from other diseases, physicians of the American Rheumatism Association have established a list of 11 abnormalities which, when combined, point to lupus.

To make a diagnosis of Lupus the patient must have had at least FOUR of these 11 manifestations at any time since the onset of the disease.

1	Malar rash	fixed red rash over the cheeks
2	Discoid rash	red patches of skin associated with scaling and plugging of the hair follicles
3	Photosensitivity	rash after exposure to sunlight
4	Mucosal ulcers	small sores that occur in mucosal lining of mouth and nose
5	Serositis	inflammation of the delicate tissues covering internal organs and abdominal pain
6	Arthritis	-very common in lupus, pain in the joints
7	Renal disorders	usually detected by routine blood and urine analysis
8	Neurological disorder	seizures or psychosis
9	Haematological disorder	haemolytic anaemia, leukopenia, thrombocytopenia
10	Immunologic disorder	tests on LE cells, anti-DNA and anti-SM antibodies
11	Anti-Nuclear Antibody (ANA blood test)	when found in the blood and the patient is not taking drugs, it is known to cause a positive test for lupus in most cases, but is not necessarily conclusive

The above criteria were laid down by the ACR in 1982.  Dr Graham Hughes  (St. Thomas' Hospital, London) has since come up with an 'alternative list of criteria'.  

---

What blood tests are done to help diagnose Lupus?

---

Full Blood Count (FBC) - Detects anaemia, low platelets, low white blood cells

Creatinine and electrolytes - Measures the salts in the blood and gives an idea of kidney function

Liver function tests - Includes measurement of liver enzymes (indicator of liver cell damage). Measures albumin (marker of kidney problem with leakage of the proteins)

ESR (Erythrocyte Sedimentation Rate) - A marker of non-specific inflammation, tends to be raised in lupus

CRP (C-reactive protein) - Another inflammatory marker, but this does NOT usually go up in Lupus

Urine - Measure protein and blood cells in urine (should be none). Identify ‘casts’ (blobs of protein escaped from the bloodstream because the kidneys are leaky)

Blood clotting tests - Tell how ‘sticky’ the blood is. Includes ‘lupus anti-coagulant’

Immunological tests

 

For more information on blood tests see the blood tests page.