Lymphocytic interstitial pneumonia J84.

Liebow and Carrington first described the clinical picture of lymphocytic interstitial pneumonia in 1969.

Pneumonia form belonging to the rare idiopathic interstitial pneumonia (rare IIPs).

The disease is very rare and accounts for only < 1% of interstitial pneumonia. It mainly affects women between 40 and 70 years of age.

The etiology is unclear.

LIP is a reactive, lymphoproliferative disease, which is why a systemic disease is usually found here, such as:

• Autoimmune diseases
• Z.n. after allogenic bone marrow transplantation
• AIDS
• Celiac disease
• Tuberculosis
• Infection with viruses (e.g. Epstein-Barr virus infection)

In the event of LIP, comprehensive diagnostics should always be carried out after the above-mentioned diseases or after underlying diseases. An idiopathic cause is possible, but very rare.

• Cough and dyspnoea as unspecific symptoms
• often symptoms of the underlying disease are indicative

In advanced stages of the disease, hypoxemia, cyanosis and often drumstick fingers are found.

Auscultation: Mostly inconspicuous. Occasionally sclerosiphonia (endinspiratory crackling) is found, preferably in the lower parts of the lung.

Chest x-ray: Diffuse interstitial basal thickening and focal compressions with positive bronchopneumogram. Often there are pneumonia-like changes and effusions, as well as dense foci in which a tumor can be excluded by differential diagnosis. As the disease progresses, these changes usually move towards the periphery. The compressions can occur both unilaterally and bilaterally.

HRCT: HRCT is the most important diagnostic measure. Thin-walled cysts of varying sizes, irregular cysts and centrilobular nodules are found. Milky glass opacities or alveolar consolidations are almost 100% present, as well as small (maximum 4 mm) centrilobular and subpleural nodules and septal thickening.

Extensive lymphocytic infiltrations are found in the alveolar septa, peribronchiolar and perivascular interstitium. The differentiation from pulmonary lymphoma is sometimes difficult. In the case of LIP, a biopsy should be performed without fail (among other things to exclude lymphoma), although any type of tissue removal - sometimes even BAL - can trigger an acute flare of disease in IPF/UIP. This is not described for the other subgroups of the.

• malignant pulmonary lymphoma
• Sarcoidosis of the lungs
• Collagenoses
• Asbestosis
• exogenous allergic alveolitis
• Langerhans cell histiocytosis

• Secondary infections (especially in AIDS and dysproteinemia); prophylactic antibiotics are NOT recommended, only close monitoring of the patient
• respiratory insufficiency
• pulmonary hypertension
• cor pulmonale

Due to the rarity of the disease there are no clear therapy recommendations. Essentially, the underlying disease should be treated.

A successful treatment with glucocorticoids or immunosuppressive drugs should be attempted if necessary.

Prednisolone:

Both the optimal dosage and the duration of treatment are not known in interstitial lung diseases. The following schemes can be found in the literature:

• Initial dose 0.5 - 1 mg/kg bw/d orally, but not more than 50 mg/d. This treatment should be carried out for 4-12 weeks and the patient should then be re-examined in detail.
• Initial dose 1 mg/kg bw/d, but not more than 50 mg/d. After 4 weeks halve the dose, after another 4 weeks halve it again and examine the patient in detail.

Azathioprine:

2 mg/kg bw/d, but not more than 150 mg/d. The dose should be increased in 50 mg steps weekly until the target dose is reached.

In case of intolerable side effects of corticosteroids or in elderly patients, prednisolone can be combined with 3 x 600 mg ACC or used as sole therapy - following the IFIGENIA study. The course of the disease does not seem to be negatively affected by this (the chronic inflammation underlying fibrosis probably reacts positively to the reduction of antioxidants).

As a rule, practically all changes in the lungs are reversible under treatment - apart from cysts.

Cysts can develop from alveolar consolidations.

As a rough guide, it can be said that 1/3 of the patients recover, 1/3 remain stable despite continuing illness and 1/3 - despite optimal treatment - the disease progresses and ultimately leads to death as a result of increasing fibrosis with respiratory insufficiency.

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