PAN -Diagnosis

Türkçe

Significant reduction of hepatitis B virus infection has also reduced the frequency of PAN in the world in parallel. In addition, some patients, previously classified as PAN, are now classified as separate diagnoses (such as MPA).

The diagnosis is mostly made at middle and advanced ages and the incidence increases with age. It makes its peak in the 6th decade of life.

It's a little more in men (1,5: 1).

Many cases are idiopathic, the pathogenesis of some patients is associated with HBV, HCV and hairy cell leukemia.

HBV-associated PAN usually develops within 4 months after HBV.

Regardless of the underlying cause, PAN is characterized by segmental transmural inflammation of musculature arteries.

PAN does not hold venues.

The cellular infiltrate consists of polymorphonuclear leukocytes and mononuclear cells.

It may be leukocytoclastosis  (fragmentation of white blood cells).

Necrosis of the arterial wall leads to a homogeneous eosinophilic appearance known as fibrinoid necrosis.

Damage to the internal and external elastic lamina may cause aneurysmal dilatation.

In the same sample, lesions at various stages can be found.

Granulomatous inflammation leads to another diagnosis. Not on the PAN.

PAN’lı hastalar tipik olarak sistemik semptom ve bulgularla gelirler.

On the skin; Purpura, tender erythematous nodules, ulcers, and bullous or vesicular eruptions may be present.

Skin lesions are more frequent in lower extremity and extremity edema is frequent. Skin lesions can be serious enough to go to gangrene.

Kidney; The most commonly affected organ in autopsy series. Renal insufficiency, hypertension, perirenal hematomas (rupture of renal artery aneurysms), multiple renal infarcts may also be present.

Incomplete narrowing of the inflamed arteries does not cause inflammation or necrosis, although it causes glomerular ischaemia. Therefore, urine examination shows sub-nephrotic proteinuria, often with minimal proteinuria and possibly moderate hematuria. However, erythrocytic eruptions, which are representative of glomerular inflammation, are not usually seen. SLE or ANCA (+) vasculitis should be considered if seen. As a result of renal ischemia, RAAS activation is considered as the cause of hypertension.

Neurological; 70% of patients have a mononeuritis multiplex. Over time, the number of affected nerves increases, so the first asymmetric involvement may return to distal symmetric polyneuropathy.

SSS involvement occurs in 5-10% patients.

GIS; The involvement of the mesenteric artery may be recognized early by abdominal pain. Because the patient is afraid of eating or because of malabsorption, weight loss may occur.

Nausea-vomiting, melena, bloody / bloodless diarrhea and GI bleeding can also be seen.

Intestinal infarction and perforation may also develop.

Splenic infarct

Patients with PAN have increased risk of perforation during colonoscopy.

Although AMI is not a very common occurrence, PAN can cause coronary ischemia.

Rarely, cholecystitis, appendicitis, segmental pancreatic infarction can occur.

Myalgia and muscle weakness are frequently observed.

Orchitis (10%)

Eye findings; Ischemic retinopathy, retinal detachment, optic neuropathy

Breast and uterine involvement

Bronchial artery involvement has been described in PAN, but other diseases should be considered if there are other parenchymal involvements due to capilleritis or vasculitis.

Diagnosis

PAN diagnosis is considered by the patient's clinic and radiological imaging, but is confirmed with biopsies from the affected organs.

The renal biopsy to be performed in the PAN can give us the pathognomonic inflammation in the middle-sized arteries. Because of the multiplicity of microaneurysms, there may sometimes be an increased risk of bleeding. Some advocate renal biopsy only if arteriography is negative.

Conventional mesenteric or renal arteriography is an alternative to biopsy.

Less invasive techniques such as CT and MRI can be used.

The PAN classification of ACR in 1990 can determine the disease with 82% sensitivity and 87% specificity.

≥ 4kg weight loss without any other explanation

Livedo reticularis

Testicular pain or tenderness

Miyaji (except shoulder and hip zone), muscle weakness, limb tenderness or polyneuropathy

Mononeuropathy or polyneuropathy

Diastolic blood pressure greater than 90 mmHg (new onset)

Elevation of serum BUN (> 40 mg / dL) or creatinine (> 1,5 mg / dL) levels.

Evidence of HBV infection

Characteristic angiographic abnormalities (other than those resulting in noninflammatory disease processes)