Cytohistologic and ElectronMicroscopic Findings inBronchoalveolar Lavage Fluidin a Case of Pulmonary AlveolarProteinosis

Dear Dr. Bedrossian:Pulmonary alveolar proteinosis (PAP) was first described

in 1958 by Rosen1 as a rare lung disorder in which thealveoli are filled with a periodic acid-schiff (PAS)-positiveproteinaceous material, rich in lipid. The exact etiology ofPAP is not clear and probably is multifactorial.1–6 Thedisease has a male predilection2 with a wide range of agefrom infants to the elderly. The patients usually present withinsidious onset of dyspnea and radiologic findings includediffuse, bilateral infiltrates7 and fluffy airspace opacificationon CT scans.8 Until the mid-1960s the diagnosis of PAPwas made mainly on clinical findings leading to open lungbiopsy. In recent years the advent and utilization of bron-choalveolar lavage (BAL) has been useful in the diagnosisand treatment of PAP.9 However, the cytological features ofPAP in BAL fluid have only been discussed in a few recentstudies.10–13 In this communication, a 28-yr-old male pa-tient is described with a history of progressive dyspnea andlung infiltrates in whom BAL was performed and the cyto-logical diagnosis of PAP was initially suggested and laterconfirmed on electron microscopy and a lung biopsy. TheBAL sample was received fresh. For cytological examina-tion, filter preparations were made on three-micron Schlei-cher and Schuell filters and stained by the Papanicolaoumethod. A portion of the material was centrifuged and cellblocks were made, fixed, embedded, cut at five microns, andstained with hematoxylin-eosin. The lung biopsy tissue wasfixed in 10% neutral buffered formalin, processed, embed-ded, cut at five microns, and stained with hematoxylin-eosin. A portion of cell block material was taken for elec-

tron microscopy (EM) and fixed in phosphate-bufferedglutaraldehyde, postfixed in osmium tetroxide, embedded inEpon, and sections were cut and stained with uranyl acetateand lead citrate and examined with an electron microscope.The BAL fluid was milky to off-whitish and showed someflocculent material. Papanicolaou-stained filter preparationsshowed few macrophages and inflammatory cells and ho-mogenous amorphous cyanophilic to basophilic granularmaterial with denser globular structures (Fig. 1). In hema-toxylin-eosin-stained sections of the cell block from theaspirate the material appeared eosinophilic, proteinaceous,and globular and was PAS-positive, diastase-resistant (Fig.2). Similar features were also noted in the lung biopsyspecimen and the material was found to fill the alveolarspaces (Fig. 3). No cholesterol clefts were found. On EM,the whorled myelin figures indicative of surfactant werenoted (Fig. 4).

PAP is an uncommon lung disease and is included in thedifferential diagnosis of patients at all ages presenting withdyspnea.1 Although in the past a diagnosis was made byopen lung biopsy, in recent years BAL cytology and/ortransbronchial biopsy have been useful in the diagnosis. Oncytologic examination amorphous, globular, cyanophilic-basophilic PAS-positive diastase-resistant material is found,generally with low numbers of macrophages and inflamma-tory cells. On EM, concentric lamellated myelin-type bodiesrepresenting surfactant are found and in lung biopsy accu-mulation of proteinaceous eosinophilic material within thealveolar spaces is present. In the case presented here theabove findings were noted and we agree with the findings ofother studies.11–13 The pathogenesis of PAP appears to berelated to surfactant production and catabolism. In differen-tial diagnosis some of the conditions to be considered in-clude Pneumocystis carinii, amiodarone and chlorphentera-mine toxicity, amyloidosis, and pulmonary infections such

*Correspondence to: Raj K Gupta MD, FIAC, Cytology Unit, Welling-ton Hospital, Wellington, New Zealand.

DOI 10.1002/dc.10112Published online in Wiley InterScience (www.interscience.wiley.com).

© 2002 WILEY-LISS, INC. Diagnostic Cytopathology, Vol 27, No 1 63

as nocardiosis, histoplasmosis, cryptococcosis, aspergillo-sis, mycobacterial diseases, candidiasis, and multiple viralinfections.4,14–16 The above differential diagnoses are ad-dressed in other studies.4,11–16 In summary, we feel thatBAL findings with the classic cytohistologic and electron-microscopic features cannot only be diagnostic of PAP butcan also minimize morbidity and mortality attributable tothis rare condition.

Raj K Gupta M.D., FIAC*St John Wakefield, Ph.D.

Sarla Naran, B.SC, CFIAC

Sharda Lallu, B.SC, CFIAC

Robert Fauck, CT(IAC)

The Cytology and Electron Microscopy UnitDepartment of Laboratory ServicesWellington Hospital and School of MedicineWellington, New Zealand

References1. Rosen SH, Castleman B, Leibow AA. Pulmonary alveolar proteinosis.

N Engl J Med 1958;258:1123–1142.

2. Larson RK, Gordinier R. Pulmonary alveolar proteinosis: report of sixcases, review of the literature, and formulation of a new theory. AnnIntern Med 1965;62:292–312.

3. Doyle AP, Balcerzak SP, Wells CL, Crittenden JO. Pulmonary alve-olar proteinosis with hematologic disorders. Arch Intern Med 1963;112:940–946.

4. Bedrossian CWM, Luna MA, Conklin RH, Miller WC. Alveolarproteinosis as a consequence of immunosuppression: a hypothesisbased on clinical and pathologic observations. Hum Pathol 1980;11:527–535.

5. Ruben FL, Talamo TS: Secondary pulmonary alveolar proteinosisoccuring in two patients with acquired immunodeficiency syndrome.Am J Med 1986;80:1187–1190.

6. Lullmann H, Lullmann-Rauch R, Wasserman O. Drug induced phos-pholipidoses. CRC Crit Rev Toxicol 1975;4:185–218.

7. Preger L. Pulmonary alveolar proteinosis. Radiology 1969;92:1291–1295.

8. Godwin JD, Muller NL, Takasugi JE. Pulmonary alveolar proteinosis:CT findings. Radiology 1988;169:609–613.

9. Ramirez-RJ. Alveolar proteinosis: importance of pulmonary lavage.Am Rev Resp Dis 1971;103:666–678.

Fig. 1. Papanicolaou-stained filter preparation in the case of PAP showingmainly granular and dense globular material and few macrophages (�320).

Fig. 2. The findings from Fig. 1 are seen in a hematoxylin-eosin-stainedsection of the cell block in the same case (�320).

Fig. 3. Hematoxylin-eosin-stained section of the open lung biopsy fromthe above case consisting of alveolar spaces filled with proteinaceousmaterial (�250).

Fig. 4. Transmission electron microscopy of a section of cell block ma-terial showing several myelin-like figures of surfactant-derived material(�4,500).

GUPTA ET AL.

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10. Mermolja M, Rott T, Debeljak A. Cytology of bronchoalveolar lavagein some rare pulmonary disorders: Pulmonary alveolar proteinosis andamiodarone pulmonary toxicity. Cytopathology 1994;5:9–16.

11. Maygarden SJ, Iacocca MV, Funkhouser WK, Novotny DB. Pulmo-nary alveolar proteinosis: a spectrum of cytologic, histochemical, andultrastructural findings in bronchoalveolar lavage fluid. Diagn Cyto-pathol 2001;24:389–395.

12. Sosolik RC, Gammon RR, Julius CJ, Ayers LW. Pulmonary alveolarproteinosis. A report of two cases with diagnostic features in bron-choalveolar lavage specimens. Acta Cytol 1998;42:377–383.

13. Burkhalter A, Silverman JF, Hopkins MB, et al. Bronchoalveolarlavage cytology in pulmonary alveolar proteinosis. Am J Clin Pathol1996;106:504–510.

14. Carlsen ET, Hill RB Jr, Rowlands DJ Jr. Nocardiosis and pulmonaryalveolar proteinosis. Ann Intern Med 1964;60:275–281.

15. Hartung M, Salfelder K. Pulmonary alveolar proteinosis and histoplas-mosis: report of three cases. Virchow Arch (Pathol Anat) 1975;368:281–287.

16. Reyes JM, Putong PB. Association of pulmonary alveolar lipoproteinosiswith mycobacterial infection. Am J Clin Pathol 1980;74:478–485.

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