Indian Journal of Pathology and Microbiology

CASE REPORT
Year
: 2014  |  Volume : 57  |  Issue : 4  |  Page : 635--637

Invasive lung infection by Scedosporium apiospermum in an immunocompetent individual


David Agatha1, Krishnan Usha Krishnan1, Ved-achalam Dillirani2, Rangam Selvi3,  
1 Department of Microbiology, Madras Medical College, Chennai, Tamil Nadu, India
2 Government Vellore Medical College, Chennai, Tamil Nadu, India
3 Stanley Medical College, Chennai, Tamil Nadu, India

Correspondence Address:
David Agatha
Institute of Microbiology, Madras Medical College, Chennai - 3, Tamil Nadu
India

Abstract

Scedosporium apiospermum previously known as Monospermum apiospermum is a ubiquitous fungus found in soil, polluted water and sewage. It causes broad spectrum of diseases, including soft tissue infections, septic arthritis, osteomyelitis, ophthalmic infections, sinusitis, pneumonia, meningitis, brain abscesses, endocarditis and disseminated infection. In recent years, it has been shown to be pathogenic for both immunocompetent and immunosuppressed patients. It is a significant opportunist with very high levels of antifungal resistance. We report here a case of invasive lung infection due to S. apiospermum in an immunocompetent patient who responded to antifungal therapy and surgical treatment.



How to cite this article:
Agatha D, Krishnan KU, Dillirani Va, Selvi R. Invasive lung infection by Scedosporium apiospermum in an immunocompetent individual .Indian J Pathol Microbiol 2014;57:635-637


How to cite this URL:
Agatha D, Krishnan KU, Dillirani Va, Selvi R. Invasive lung infection by Scedosporium apiospermum in an immunocompetent individual . Indian J Pathol Microbiol [serial online] 2014 [cited 2020 Jan 20 ];57:635-637
Available from: http://www.ijpmonline.org/text.asp?2014/57/4/635/142716


Full Text

 INTRODUCTION



Scedosporium apiospermum was first described as a human pathogen in 1911 by Saccardo in an Italian patient with mycetoma. [1] In recent years, an increasing number of infections caused by S. apiospermum is being encountered. This fungus may reach the lungs and bronchial tree causing a wide range of manifestations, from colonization of airways to deep pulmonary infections. Frequently they may also disseminate to other organs, with a predilection for the brain. In otherwise healthy patients, the infection is characterized by non-invasive type involvement, while invasive and or disseminated infections are mostly seen in immunocompromised patients.

 CASE REPORT



A 47year old man was admitted to the medical ward with complaints of hemoptysis for 3 days. He gave the history of cough with expectoration and breathlessness on exertion on and off for the past 1 year. He had a past history of pulmonary tuberculosis 6 years ago. Chest X-ray showed homogenous opacity midzone, left side with bilateral minimal non-homogenous infiltrate. Interpretation of the CT scan of the lung was left lower lobe aspergilloma. Based on the clinical findings, chest X-ray and CT scan findings clinical diagnosis of aspergilloma of left lung was made. Other blood parameters were within normal limits. Sputum specimen was subjected to bacterial and fungal culture. The patient was empirically started on injection amphotericin and broad-spectrum antibiotics.

KOH mount of the sputum revealed acute angle branching septate hyaline hyphae. Fungal culture on Sabouraud's dextrose agar after 1week of incubation showed mousy gray woolly growth with a grayish black reverse. Lactophenol cotton blue mount showed septate hyaline hyphae with elliptical single-celled conidia borne singly from the tips of long or short conidiophores [Figure 1]. The fungus was identified as S. apiospermum. Sputum bacterial and mycobacterial culture was negative. After the isolation of Scedosporium the patient was treated with itraconazole for 4weeks as Scedosporium is almost always resistant to amphotericin.{Figure 1}

Left upper lobectomy and segmentectomy of apical segment of left lower lobe was performed. The lobectomy specimen was subjected to histopathological examination and fungal culture. On histhopathological examination,cross-sectional study of the lobectomy specimen revealed a cavity measuring 6 × 4 4.5 cm containing yellowish brown material as well as sectional study showed septate fungal hyphae with acute angle branching, area of necrosis and acute inflammatory infiltrate [Figure 2]. The impression was aspergillosis lung. S. apiospermum was isolated from fungal culture of lobectomy specimen.

Post operatively the patient developed left pleural effusion and bronchopleural fistula for which closure and repair were done successfully. He completed the antifungal regimen, recovered fully and was discharged.{Figure 2}

 DISCUSSION



0S. apiospermum is a filamentous fungi that is found world wide. Pseudallescheria boydii is a perfect state of the anamorphs S. apiospermum and Graphium eumorphum. The perfect state is characterized by production of globose brown to black cleistothecia in clusters and pale yellow to golden brown,lemon-shaped ascospores. [2] Strains without ascomata can be recognized by their two typical anamorphs ie. S. apiospermum and Graphium eumorphum.

Three basic clinical syndromes can be distinguished for S. apiospermum:

Localized disease after trauma (found in otherwise healthy persons). Largely asymptomatic or symptomatic colonization of cavities (Pulmonary cases are observed in patients with predisposing pulmonary disorders) and Systemic invasive disease (occurs if the immune status of the patient is severely impaired or in victims of near-drowning).

Mycetoma is one of the classical entities of localized disease of S. apiospermum. Arthritis, osteomyelitis, eye infections and onychomycosis are the other localized diseases.

Symptomatic colonization of cavities due to S. apiospermum include pulmonary fungus ball, allergic bronchopulmonary Scedosporium pneumonia (ABSP) and pulmonary colonization in cystic fibrosis (CF). Pulmonary fungus ball due to S. apiospermum occurs in patients with a chronic pulmonary infiltrate from a previously or underlying disorder, such as sarcoidosis or tuberculosis, [3] but the fungus may also be the primary cause of disease and may occur in otherwise healthy patients. [4] Allergic bronchopulmonary pneumonia can also be caused by S. apiospermum[5] due to the inflammatory response triggered by colonization of the fungus. The disorder is characterized by the presence of obvious plugs in sputum containing S. apiospermum cells. Colonization of the respiratory tract with S. apiospermum is usually asymptomatic in patients with cystic fibrosis. [6]

It causes Scedosporium pneumonia in systemic invasive disease. Scedosporium pneumonia is characterized by the frequent occurrence of numerous intercommunicating cavities, fibrosis, and granules. Patients are mostly symptomatic with impaired respiratory function. Hemoptysis is frequently observed. It occurs in cases with pre-existing pulmonary disorders, such as tuberculosis, sarcoidosis, lung transplant, chronic bronchitis and bacterial pneumonia. It may occur in otherwise healthy hosts. Endocarditis, CNS infections, disseminated infections are the other invasive diseases.

This is a case of invasive lung infection due to S. apiospermum who presented with hemoptysis. The colonization of fungus in cysts,cavities and ectatic bronchi of patients with prior tuberculosis or other chronic lung disease ultimately result in productive cough or hemoptysis. [7] Culture of sputum and lobectomy specimen for fungus yielded S. apiospermum. HPE was reported as aspergillosis lung. Fungus can often be identified in tissue even in the absence of culture by taking into account the clinical condition, tissue inflammatory response, and appearance of fungus. But culture diagnosis is potentially more accurate than histologic features as the S. apiospermum is histopathologically analogous to Aspergillus species. [7] As the Scedosporium species are found to be resistant to amphotericin B and flucytosine, the patient was treated with itraconazole for 4 weeks. Although voriconazole is considered as first-line treatment by some, [8] several reports have shown itraconazole, an imidazole derivative, to be effective in the treatment. [9]

Cultural substantiation of the fungal isolate in the diagnosis is pertinent to have an effective treatment. [7] Surgical resection of localized lesion remains a key to successful outcome. [7]

The present case highlights the importance of culture diagnosis of S. apiospermum infection to institute the appropriate antifungal therapy.

References

1Schwartz DA. Pseudallescheriasis and Scedosporiasis. In: Connor DH, Chandler FW, editors. Pathology of Infectious Diseases. Stamford: Appelton and Lange; 1997. p. 1073-9.
2Forbes BA, Sahm DF, Weissfeld AS. In: Bailey and Scott's Diagnostic Microbiology, 12 th ed. Laboratory Methods in basic mycology, Mycology. Chapter 50. St. Louis: Mosby Publishers; 2007. p. 633.
3Rippon JW. Clinical spectrum of petriellidosis: Mycetoma to systemic opportunistic. Pan Am Health Org Sci Publ 1980;396:276-95.
4Zaas D. Cases from the Osler Medical Service at Johns Hopkins University. Scedosporium apiospermum mycetoma of the lung. Am J Med 2002;113:760-2.
5Miller MA, Greenberger PA, Amerian A, Toogood JH, Noskin GA, Roberts M, et al. Allergic bronchopulmonary mycosis caused by Pseudallescheria boydii. Am Rev Respir Dis 1993;148:810-2.
6Chabasse D, Bouchara JP, Chazalette JP, Carrere J, Genes JL, Cimon B. Mucoviscidosis and fungal colonization by Scedosporium apiospermum. J Mycol Med 1991;1:152-5.
7Chander J. A text book of Medical Mycology, 3 rd ed. Chapter 29. New Delhi, India: Mehta Publishers; 2008. p. 423-5.
8Tamm M, Malouf M, Glanville A. Pulmonary scedosporium infection following lung transplantation. Transpl Infect Dis 2001;3:189-94.
9Liu YF, Zhao XD, Ma CL, Li CX, Zhang TS, Liao WJ. Cutaneous infection by Scedosporium apiospermum and its successful treatment with itraconazole. Clin Exp Dermatol 1997;22:198-200.