There are several Interstitial Pneumonias. In the 1960's, Professor Liebow used the term usual interstitial pneumonia (UIP) for the most common form. He described "Desquamative Interstitial Pneumonia (DIP), Lymphocytic Interstitial Pneumonia (LIP), and Giant Cell Interstitial Pneumonia (GIP).

These are chronic disorders with specific types of cells, inflammation, and varying degrees of scarring. Katzenstein later described Nonspecific Interstitial Pneumonia (NIP or NSIP), which is now the second most common type of chronic interstitial pneumonia. The is also an Acute Interstitial Pneumonia (AIP), which develops within a few days.

The diagnosis of these pneumonias is based on symptoms, physical findings of crackles, pulmonary functions studies showing decreased diffusing capacity, and the radiographic studies. A lung biopsy by a VAT procedure is needed to confirm these specific types of interstitial pneumonia.

Acute Interstitial Pneumonia (AIP)

AIP is a rare, distinct respiratory illness. Katzenstein first described AIPin 1986. Among four patients with interstitial pneumonia described by Drs. Hamman and Rich in 1944, three of them had AIP. This illness is sometimes referred to as "Hamman-Rich disease". 

The microscopic findings of the lung tissue show fibrosis of the interstitium and diffuse damage of the alveoli (small spherical oxygen exchange units). The specific and distinctive finding of AIP is "hyaline membrane formation". The cause of AIP is not known. AIP occurs in men and women with equal frequency, and at all ages.

Most patients have symptoms for less than three weeks. Many have an associated flu-like illness or febrile illness. There is a rapid onset of shortness of breath and respiratory failure. AIPis usually so severe that hospital care is required, often in the ICU (intensive care unit). The oxygen value may be severely decreased.

The chest x-ray in AIP shows dense infiltrates in both sides. The chest CT scan confirms these infiltrates and in some situations, may show honeycombing. A lung biopsy for tissue is required for the diagnosis. Tissue is obtained from a video-assisted thoracoscopy (VAT) procedure or from a small lung operation.

Corticosteroid therapy is the best treatment option for AIP, but individuals may not respond. This medication is often given intravenously while in the ICU or hospital setting. Cytoxan may be given either in conjunction with the corticosteroid or after failure to show improvement. Outcome can be poor, survival rates range as low of 15% and has high as 40%. Lung transplantation can be a life-saving procedure in this situation; however, sometimes patients are too ill or unstable to undergo the procedure, or a donor lung cannot be found in time.

AIP References:

1. Katzenstein AL, Myers JL, Mazur MT. Acute interstitial pneumonia (AIP). A clinicopathologic, ultrastructural, and cell kinetic study. Am J Surg Pathol. 1986 Apr; 10(4): 256-267. PMID: 3706612.

2. Olson J, Colby TV, Elliott CG. Hamman-Rich syndrome revisited. Mayo Clin Proc. 1990 Dec; 65(12):1538-1548. PMID: 2255216.

3. Johkoh T, Muller NL, Taniguchi H, Kondoh Y, Akira M, Ichikado K, Ando M, Honda O, Tomiyama N, Nakamura H.Acute interstitial pneumonia (AIP): thin-section CT findings in 36 patients. Radiology. 1999 Jun; 211(3): 859-863. PMID: 10352616.

4. Bouros D, Nicholson AC, Polychronopoulos V, du Bois RM. Acute interstitial pneumonia (AIP). Eur Respir J. 2000 Feb; 15(2): 412-8. PMID: 10706513.

5. Vourlekis JS, Brown KK, Cool CD, Young DA, Cherniack RM, King TE, Schwarz MI. Acute interstitial pneumonitis (AIP). Case series and review of the literature. Medicine (Baltimore). 2000 Nov; 79(6): 369-78. PMID: 11144035.

6. Ichikado K, Suga M, Muller NL, Taniguchi H, Kondoh Y, Akira M, Johkoh T, Mihara N, Nakamura H, Takahashi M, Ando M. Acute interstitial pneumonia (AIP): comparison of high-resolution computed tomography findings between survivors and nonsurvivors. Am J Respir Crit Care Med. 2002 Jun 1; 165(11): 1551-1556. PMID: 12045132.

Nonspecific Interstitial Pneumonia (NIP)

NIP has been described as a distinct respiratory illness by Katzenstein and colleagues in 1994, and has emerged as the second most common type of chronic interstitial pneumonia second to Usual Interstitial Pneumonia (UIP). The abbreviation "NSIP" is sometimes used.

The microscopic findings of the lung tissue in NIP are characterized by interstitial infiltrate and three patterns of fibrosis (scar). In one-half of patients, there is little or no fibrosis. In one-third of patients there is moderate fibrosis. In about 15%, the fibrosis is dense. There is a favorable response to corticosteroid therapy for individuals with the first and second pattern. 

The cause of NIP is usually not known. The lesion has been associated with the connective tissue disorders, inhalation of toxic agents, and sometimes associated with acute lung injury from a recent surgery, and severe pneumonia or ARDS (adult respiratory distress syndrome).  NIP occurs equally in men and women and at all ages, usually 40 to 70 years. Shortness of breath is the most common symptom and may be associated with cough. Crackles are common. The average duration of the illness is 8 months.  The chest x-ray in NIP shows patchy infiltrates in both lungs and sometimes small linear opacities at the lung bases. The CT scan confirms these fluffy infiltrates and does not show honeycombing. A lung biopsy for tissue is required for the diagnosis. Tissue is obtained from a video-assisted thoracoscopy (VAT) or from a small lung operation. This may be performed on a day-surgical basis if the individual is stable or in the hospital if the individual is severely ill. Corticosteroid therapy is the best treatment option for NIP. The outcome is fairly good, 50% of patients are cured and a higher percentage of patients are stabilized. Slightly less that 15% of patients die from this disorder.  A favorable response is directly related to the amount of fibrosis and scar seen in the lung biopsy. Individuals with no scar have an excellent chance for cure, while individuals with dense scar have a less favorable course. Lung transplantation offers an alternative treatment for individuals with the dense scarring.

NIP References:

1. Katzenstein AL, Fiorelli RF. Nonspecific interstitial pneumonia/fibrosis (NIP). Histologic features and clinical significance. Am J Surg Pathol. 1994 Feb; 18(2): 136-147.

PMID: 8291652.

2. Katzenstein AL, Myers JL. Nonspecific interstitial pneumonia (NIP) and the other idiopathic interstitial pneumonias: classification and diagnostic criteria. Am J Surg Pathol. 2000 Jan; 24(1): 1-3. PMID: 10632482.

3. Flaherty KR, Travis WD, Colby TV, Toews GB, Kazerooni EA, Gross BH, Jain A, Strawderman RL, Flint A, Lynch JP, Martinez FJ. Flaherty KR, Travis WD, Colby TV, Toews GB, Kazerooni EA, Gross BH, Jain A, Strawderman RL, Flint A, Lynch JP, Martinez FJ. Histopathologic variability in usual (UIP) and nonspecific interstitial pneumonias (NIP). Am J Respir Crit Care Med. 2001 Nov 1; 164(9): 1722-1727. PMID: 11719316.

4. Kim DS, Yoo B, Lee JS, Kim EK, Lim CM, Lee SD, Koh Y, Kim WS, Kim WD, Colby TV, Kitiaichi M. The major histopathologic pattern of pulmonary fibrosis in scleroderma is nonspecific interstitial pneumonia (NIP). Sarcoidosis Vasc Diffuse Lung Dis. 2002 Jun; 19(2): 121-127. PMID: 12108451.

X-ray Findings:

1. Kim EY, Lee KS, Chung MP, Kwon OJ, Kim TS, Hwang JH. Nonspecific interstitial pneumonia with fibrosis (NIP): serial high-resolution CT findings with functional correlation. AJR Am J Roentgenol. 1999 Oct; 173(4): 949-953.

2. MacDonald SL, Rubens MB, Hansell DM, Copley SJ, Desai SR, du Bois RM, Nicholson AG, Colby TV, Wells AU.Nonspecific interstitial pneumonia (NIP) and usual interstitial pneumonia (UIP): comparative appearances at and diagnostic accuracy of thin-section CT. Radiology. 2001 Dec; 221(3): 600-605. PMID: 11719652.

3. Johkoh T, Muller NL, Colby TV, Ichikado K, Taniguchi H, Kondoh Y, Fujimoto K, Kinoshita M, Arakawa H, Yamada H, Suga M, Ando M, Koyama M, Nakamura H. Nonspecific interstitial pneumonia (NIP): correlation between thin-section CT findings and pathologic subgroups in 55 patients. Radiology. 2002 Oct; 225(1): 199-204. PMID: 12355005.

Treatment:

1. Nanki N, Fujita J, Yamaji Y, Maeda H, Kurose T, Kaji M, Satoh K, Miyatani K, Yamadori I, Ohtsuki Y, Ishida T.Nonspecific interstitial pneumonia/fibrosis (NIP) completely recovered by adding cyclophosphamide to corticosteroids. Intern Med. 2002 Oct; 41(10): 867-870. PMID: 12413012.

Outcome:

1. Nagai S, Kitaichi M, Itoh H, Nishimura K, Izumi T, Colby TV. Idiopathic nonspecific interstitial pneumonia/fibrosis (NIP): comparison with idiopathic pulmonary fibrosis and BOOP.

Eur Respir J. 1998 Nov; 12(5): 1010-1019. PMID: 9863989.

2. Cottin V, Donsbeck AV, Revel D, Loire R, Cordier JF.Nonspecific interstitial pneumonia (NIP). Individualization of a clinicopathologic entity in a series of 12 patients. Am J Respir Crit Care Med. 1998 Oct; 158(4): 1286-1293. PMID: 9769293.

3. Daniil ZD, Gilchrist FC, Nicholson AG, Hansell DM, Harris J, Colby TV, du Bois RM. A histologic pattern of nonspecific interstitial pneumonia (NIP) is associated with a better prognosis than usual interstitial pneumonia (UIP) in patients with cryptogenic fibrosing alveolitis. Am J Respir Crit Care Med. 1999 Sep; 160(3): 899-905. PMID: 10471616.

4. Travis WD, Matsui K, Moss J, Ferrans VJ. Idiopathic nonspecific interstitial pneumonia (NIP): prognostic significance of cellular and fibrosing patterns: survival comparison with usual interstitial pneumonia (UIP) and desquamative interstitial pneumonia (DIP). Am J Surg Pathol. 2000 Jan; 24(1): 19-33. PMID: 10632484.

5. Riha RL, Duhig EE, Clarke BE, Steele RH, Slaughter RE, Zimmerman PV. Survival of patients with biopsy-proven usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NIP). Eur Respir J. 2002 Jun; 19(6): 1114-1118. PMID: 12108865.

6. Bouros D, Wells AU, Nicholson AG, Colby TV, Polychronopoulos V, Pantelidis P, Haslam PL, Vassilakis DA, Black CM, du Bois RM. Histopathologic subsets of fibrosing alveolitis in patients with systemic sclerosis and their relationship to outcome. Am J Respir Crit Care Med. 2002 Jun 15; 165(12): 1581-1586. PMID: 12070056.

Desquamative Interstitial Pneumonia (DIP)

DIP is a specific term for a lung disorder that shows a homogenous process of large inflammation cells filling the alveoli (spherical oxygen exchange units). These cells appear "desquamated" or peeled off of the alveolar walls, giving the disorder its name. The lungs have a homogeneous pattern of these cells. There is a variable amount of interstitial scarring associated with the disorder.

The cause of DIP is usually not known; however, more than 90% of individuals with DIP smoke cigarettes. DIP may occur in individuals with the rheumatological disorders such as lupus erythematosus or rheumatoid arthritis. DIP occurs in men and women aged 30 to 60. Shortness of breath is usually the initial symptom, and there may be an associated flu-like illness.  Crackles are commonly heard through the stethoscope.

The lung function studies show decreases in the vital capacity and the diffusing capacity. The chest x-ray usually shows small linear opacities at the lung bases. Fluffy infiltrates may occur. Honeycomb appearance occurs in 10%-15% of individuals.

Examination of lung tissue is required for the diagnosis of DIP. The tissue can be obtained from a video-assisted thoracoscopy (VAT) or from a small lung operation. The VAT is performed in a day surgical setting and a small tube in the chest is needed for 24 to 48 hours.

Prednisone is currently the best medication for treatment of DIP. The dosage is usually high initially at 60 mg and then is gradually decreased as the disease responds. The outcome is fairly good, 50% of patients are cured. The survival rate is 90% at 5 years and 70% at 10 years. Lung transplantation may be utilized in certain situations.

DIP References:

1. Carrington CB, Gaensler EA, Coutu RE, FitzGerald MX, Gupta RG. Natural history and treated course of usual (UIP) and desquamative interstitial pneumonia (DIP). N Engl J Med. 1978 Apr 13; 298(15): 801-809. PMID: 634315.

2. Heyneman LE, Ward S, Lynch DA, Remy-Jardin M, Johkoh T, Muller NL. Respiratory bronchiolitis (RB), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), and desquamative interstitial pneumonia (DIP): different entities or part of the spectrum of the same disease process? AJR Am J Roentgenol. 1999 Dec; 173(6): 1617-1622. PMID: 10584810.

3. Travis WD, Matsui K, Moss J, Ferrans VJ. Idiopathic nonspecific interstitial pneumonia (NIP): prognostic significance of cellular and fibrosing patterns: survival comparison with usual interstitial pneumonia (UIP) and desquamative interstitial pneumonia (DIP). Am J Surg Pathol. 2000 Jan; 24(1): 19-33. PMID: 10632484.

4. Ryu JH, Colby TV, Hartman TE, Vassallo R. Smoking-related interstitial lung diseases: a concise review. Eur Respir J. 2001 Jan; 17(1): 122-132. PMID: 11307741.

Lymphocytic Interstitial Pneumonia (LIP)

LIP (lymphocytic interstitial pneumonia) is a rare lung disease that is characterized by the presence of numerous cells called lymphocytes in the interstitial regions. There is a variable degree of scarring.

The cause of LIP is not known. LIP may occur in association with autoimmune diseases, most often Sjogren's syndrome. LIP occurs with a two-fold increase among women as compared to men aged 40 to 70 years. Shortness of breath and cough are common symptoms. Crackles are sometimes heard. The chest x-ray shows small linear opacities at the lung bases. The chest CT scan sometimes show cystic structures. A lung biopsy for tissue is required for the diagnosis. Tissue is obtained from a video-assisted thoracoscopy (VAT) or from a small lung operation. This may be performed on a day-surgical basis if the individual is stable or in the hospital if the individual is severely ill. Corticosteroid therapy is generally the treatment that is used. It is not clear whether the treatment is effective. In about one-third of individuals, the illness eventually disappears. There are chronic symptoms in others. One-third to one-half of individuals may die from this disorder within 5 years.

LIP References:

1. Teirstein AS, Rosen MJ. Lymphocytic interstitial pneumonia (LIP). Clin Chest Med. 1988 Sep; 9(3): 467-571. PMID: 3044682.

2. Swigris JJ, Berry GJ, Raffin TA, Kuschner WG. Lymphoid interstitial pneumonia (LIP). Chest. 2002 Dec; 122(6): 2150-2164. PMID: 12475860.

Giant Cell Interstitial Pneumonia (GIP)

GIP (giant cell interstitial pneumonia) is a very rare lung disease that is usual caused by high levels of exposure to cobalt during the production or grinding of "hard metal" drill bits and other products. The process is characterized by inflammation, specific cells called giant cells, and a variable amount of scarring.

Shortness of breath is the most common symptom. Crackles are sometimes heard. The chest x-ray shows small linear opacities at the lung bases. A lung biopsy for tissue is required for the diagnosis. Corticosteroid therapy is generally the treatment used with variable success. Several individuals have died from this disease. Lung transplantation may be beneficial in certain situations.

GIP references:

1. Daroca PJ Jr, George WJ. Giant cell interstitial pneumonia (GIP). South Med J. 1991 Feb; 84(2): 257-263. PMID: 1990465.

2. Ohori NP, Sciurba FC, Owens GR, Hodgson MJ, Yousem SA. Giant-cell interstitial pneumonia (GIP) and hard-metal pneumoconiosis. A clinicopathologic study of four cases and review of the literature. Am J Surg Pathol. 1989 Jul; 13(7): 581-587. PMID: 2660610.

3. Lee SM, Moon CH, Oh YB, Kim HY, Ahn Y, Ko EJ, Joo JE.Giant-cell interstitial pneumonia (GIP) in a gas station worker. J Korean Med Sci. 1998 Oct; 13(5) :545-547. PMID: 9811187.

4. Kinoshita M, Sueyasu Y, Watanabe H, Tanoue S, Okubo Y, Koga T, Kawahara M, Nagata E, Oizumi K. Giant cell interstitial pneumonia (GIP) in two hard metal workers: the role of bronchoalveolar lavage in diagnosis. Respirology. 1999 Sep; 4(3): 263-266. PMID: 10489670.

5. Kakugawa T, Mukae H, Nagata T, Ishii H, Kaida H, Hayashi T, Suematsu T, Kadota J, Kohno S. Giant cell interstitial pneumonia (GIP) in a 15-year-old boy. Intern Med. 2002 Nov; 41(11): 1007-1012. PMID: 12487179.

What are the Other Interstitial Lung Diseases?

Interstitial Lung Diseases (ILD) is a general term used for disorders involving the interstitium The interstium is a term used for the support structures of the lung and the tissue in between the alveoli (spherical air-exchange units). There are several hundred types of interstitial lung diseases.

There are three major groups of interstitial lung disease. First, the interstitial pneumonias that include usual interstitial pneumonia (UIP) and others. Second, the granulomatous disorders that include sarcoidosis and hypersensitivity pneumonia. Third, the miscellaneous disorders that include bronchiolitis obliterans organizing pneumonia (BOOP), acute and chronic eosinophilic pneumonia (AEPand CEP), pulmonary alveolar proteinosis (PAP), amyloidosis, lymphangioleiomyomatosis (LAM), carcinomatosis.  These disorders are diagnosed by the symptoms, physical findings, radiographic studies, and pulmonary function tests. A lung biopsy may be needed so that the microscopic findings of the tissue can be interpreted by the lung pathologist.

Acute Eosinophilic Pneumonia (AEP)

AEP is a rare, distinct respiratory illness. Dr. Allen first described AEPin 1989 and Dr. Tazelaar further characterized the illness in 1997. The microscopic findings of the lung tissue shows diffuse alveolar damage and inflammation of the lungs characterized by huge numbers of a red-staining cell called an eosinophil in the interstitial regions and alveoli (spherical oxygen exchange units in the lung).

The cause of AEP is not known. There are no associated parasitic, fungal or bacterial infections. The disease affects patients of all ages and equally among men and women. The illness develops rapidly in less than five days with respiratory failure and fever, shortness of breath, chest pain and achy joints. These symptoms prompt an admission to the hospital or to the ICU (intensive care unit). The chest x-ray shows diffuse fluffy abnormalities in both lungs. The chest CT scan confirms the diffuse nature of the infiltrates. The diagnosis is obscure at this point and a lung biopsy is required to establish the diagnosis of AEP. The tissue is obtained from a video-assisted thoracoscopy (VAT) although a report in 2002 suggests that bronchoalveolar lavage (obtaining cells from the lung by performing a bronchoscopy) showing more than 50% of eosinophils (the red-staining white cells) can be utilized to establish a diagnosis.  Fortunately, corticosteroid therapy, usually intravenously at first, results in a prompt and complete response. A one to two week course of prednisone results in a cure. The prognosis is excellent, there has only been one patient reported to have died, not from the AEP, but from a severe respiratory infection.

AEP References:

1. Nishio M, Ohata M, Suruda T, Uetani K, Kobayashi H, Funasako M. Idiopathic acute eosinophilic pneumonia (AEP). Intern Med. 1992 Sep; 31(9): 1139-1143.

2. Pope-Harman AL, Davis WB, Allen ED, Christoforidis AJ, Allen JN. Acute eosinophilic pneumonia (AEP). A summary of 15 cases and review of the literature. Medicine (Baltimore). 1996 Nov; 75(6): 334-342. PMID: 8982150.

3. Tazelaar HD, Linz LJ, Colby TV, Myers JL, Limper AH.Acute eosinophilic pneumonia (AEP): histopathologic findings in nine patients. Am J Respir Crit Care Med. 1997 Jan; 155(1): 296-302. PMID: 9001328.

4. Watanabe K, Fujimura M, Kasahara K, Yasui M, Myou S, Kita T, Watanabe A, Nakao S. Acute eosinophilic pneumonia (AEP) following cigarette smoking: a case report including cigarette-smoking challenge test. Intern Med. 2002 Nov; 41(11): 1016-1020. PMID: 12487181.

5. Philit F, Etienne-Mastroianni B, Parrot A, Guerin C, Robert D, Cordier JF. Idiopathic acute eosinophilic pneumonia (AEP): a study of 22 patients. Am J Respir Crit Care Med. 2002 Nov 1; 166(9): 1235-1239. PMID: 12403693.

Chronic Eosinophilic Pneumonia (CEP)

CEP is a rare respiratory illness that was described by Dr. Carrington in 1969. The microscopic findings of the lung tissue show huge numbers of a red-staining cell called an eosinophil in the interstitial regions and alveoli (spherical oxygen exchange units in the lung). These cells are also seen in an organized pattern in the small bronchiole airways and in the alveoli.

The cause of CEP is unknown in most situations. The CEP pattern may occur with certain types of medications such as the anti-cancer drugs or antibiotics. The disease occurs more often in women than men and at all ages. There may be previous asthma. Individuals may be "atopic", which is a familial predilection to skin allergies. Testing of the blood often shows a high percentage of eosinophils.

Sometimes the illness develops as a mild flu-like process for six to eight weeks, but often symptoms are severe and disabling for three months or more. Shortness of breath, cough, and weight loss are common. Fever occurs in virtually all individuals and drenching sweats are frequent.  The chest x-ray often shows a distinctive pattern. This consists of fluffy or patchy infiltrates in the periphery of the lungs. These are often fleeting or migratory in nature, occurring in the upper lungs for a few days, then in the lower lung or mid lung region.

CEP is one of the unusual situations where the illness can be treated with an "empirical trial" of corticosteroid medication, which is when a medication is given for a specific length of time to "see if it works". Since the process is eosinophilic inflammation, the anti-inflammation medication prednisone is used for treatment. There is such a rapid and sustained response to this treatment, usually in 48 to 72 hours, the diagnosis can be established in three to five days.

The empirical trial is only utilized in individuals with the typical symptoms, increased eosinophils in the blood and the typical x-ray pattern. For others, a lung biopsy is required to establish the diagnosis . The tissue is obtained from a video-assisted thoracoscopy (VAT) or from a small lung operation. For severely ill patients, this is performed in the hospital. The procedure may also be performed on a day-surgical basis with one or two nights of observation.

Sometimes no treatment is given and the illness resolves spontaneously. For most patients, corticosteroid therapy, intravenously in the hospital or in the form of prednisone, is given. It results in a rapid response, often within a few hours. The treatment is usually given for less than six moths. However, unlike, acute eosinophilic pneumonia (AEP), in the chronic form (CEP), recurrences are frequent.

Fortunately, the second, third or more frequent relapse will respond to treatment. Prolonged treatment does not predict relapses, so each occurrence is treated individually. The over all outcome is good. Death from CEP has been reported in rare situations.

CEP references:

1. Carrington CB, Addington WW, Goff AM, Madoff IM, Marks A, Schwaber JR, Gaensler EA. Chronic eosinophilic pneumonia (CEP). N Engl J Med. 1969 Apr 10; 280(15): 787-798. PMID: 5773637.

2. Gaensler EA, Carrington CB. Peripheral opacities in chronic eosinophilic pneumonia (CEP): the photographic negative of pulmonary edema. AJR Am J Roentgenol. 1977 Jan; 128(1): 1-13. PMID: 401562.]

3. Yoshida K, Shijubo N, Koba H, Mori Y, Satoh M, Morikawa T, Abe S. Chronic eosinophilic pneumonia (CEP) progressing to lung fibrosis. Eur Respir J. 1994 Aug; 7(8): 1541-1544. PMID: 7957844.

4. Marchand E, Reynaud-Gaubert M, Lauque D, Durieu J, Tonnel AB, Cordier JF. Idiopathic chronic eosinophilic pneumonia (CEP). A clinical and follow-up study of 62 cases. Medicine (Baltimore). 1998 Sep; 77(5): 299-312. PMID: 9772920.

5. Arakawa H, Kurihara Y, Niimi H, Nakajima Y, Johkoh T, Nakamura H. Bronchiolitis obliterans with organizing pneumonia (BOOP) versus chronic eosinophilic pneumonia (CEP): high-resolution CT findings in 81 patients. AJR Am J Roentgenol. 2001 APR; 176(4): 1053-1058. PMID: 11264110.

6. Samman YS, Wali SO, Abdelaal MA, Gangi MT, Krayem AB. Chronic eosinophilic pneumonia (CEP) presenting with recurrent massive bilateral pleural effusion. Chest. 2001 Mar; 119(3): 968-970. PMID: 11243986.

Respiratory Bronchiolitis-Interstitial Lung Disease (RB-ILD)

RB-ILD is a very rare lung disorder caused by cigarette smoking. Shortness of breath is the most common symptom. Crackles are heard through the stethoscope. The vital capacity and the diffusing capacity are usually decreased. The chest x-ray shows patchy infiltrates and reticular-nodular opacities at the lung bases. The chest CT scan may show some regions of "ground glass" opacity. A lung biopsy is needed to confirm the diagnosis.

The outcome is usually good if the individual stops smoking. Sometimes, a course of corticosteroid therapy is needed for treatment.

RB-ILD references:

1. Myers JL, Veal CF Jr, Shin MS, Katzenstein AL.Respiratory bronchiolitis causing interstitial lung disease (RB-ILD). A clinicopathologic study of six cases. Am Rev Respir Dis. 1987 Apr; 135(4): 880-884. PMID: 3565934.

2. Yousem SA, Colby TV, Gaensler EA. Respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) and its relationship to desquamative interstitial pneumonia (DIP). Mayo Clin Proc. 1989 Nov; 64(11): 1373-1380. PMID: 2593722.

3. Heyneman LE, Ward S, Lynch DA, Remy-Jardin M, Johkoh T, Muller NL. Respiratory bronchiolitis (RB), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), and desquamative interstitial pneumonia (DIP): different entities or part of the spectrum of the same disease process? AJR Am J Roentgenol. 1999 Dec; 173(6): 1617-1622. PMID: 10584810.

4. McWilliams AM, Lake FR. Respiratory bronchiolitis associated interstitial lung disease (RB-ILD) presenting with haemoptysis. Respirology. 2000 DEC; 5(4): 385-387. PMID: 11192551.

5. Park JS, Brown KK, Tuder RM, Hale VA, King Jr TE, Lynch DA. Respiratory bronchiolitis-associated interstitial lung disease (RB-ILD): radiologic features with clinical and pathologic correlation. J Comput Assist Tomogr. 2002 Jan-Feb; 26(1): 13-20. PMID: 11801899.