Introduction
Chromoblastomycosis (also known as black blastomycosis, verrucose dermatitis, cutaneous chromoblastomycosis, chromomycotic verrucose dermatitis, blastomycotic verrucose dermatitis, Pedroso's disease and Fonseca's disease) is a fungal infection of the skin and subcutaneous tissue.Reference López Martínez and Méndez Tovar1Fonsecaea pedrosoi is the most common agent, accounting for 70–90 per cent of cases worldwide. Some of the other less common agents include Phialophora verrucosa, Cladophialophora carrionii and Fonsecaea compacta.Reference López Martínez and Méndez Tovar1, Reference Ameen2 These saprophytes, which are found in soils and plants in tropical and subtropical climates, cause infection following traumatic inoculation into the skin.Reference López Martínez and Méndez Tovar1–Reference Minotto, Benardi, Mallmann, Edelweiss and Scroferneker3
Madagascar, South Africa, Brazil and Costa Rica have the highest prevalence of this disease; however, many other countries, including Malaysia, India and Nepal, have reported cases of chromoblastomycosis.Reference López Martínez and Méndez Tovar1, Reference Yap, Chromoblastomycosis in and East Malaysian4–Reference Pradhan, Talwar, Ghosh, Swami, Shiva Raj and Gupta6 The infection may present as a papule, nodule, scaly plaque, or verrucose, exophytic or cauliflower-like mass. The feet and lower limbs are commonly implicated (as these are more prone to trauma),Reference Ameen2, Reference Minotto, Benardi, Mallmann, Edelweiss and Scroferneker3 but any part of the body may be affected.Reference Minotto, Benardi, Mallmann, Edelweiss and Scroferneker3 This paper reports a rare case of chromoblastomycosis occurring in the nasal cavity.
Case report
A 50-year-old Malaysian gentleman, who worked in a rubber tree plantation in the southern state of Johor, presented to an ENT clinic in July 2013 with a history of bleeding from the left side of the nose. He reported a one-year history of mild, intermittent nosebleeds. He did not complain of fever, or a blocked or runny nose. He could not recall any past significant nasal injury.
Endoscopic examination revealed a pale yellowish, nodular mass at the anterior end of the inferior edge of the left middle turbinate, measuring approximately 1.5 × 1.5 cm (Figure 1). There was no active bleeding from the lesion at that time. Other areas of the nose and nasopharynx were normal. Examination of the oral cavity and neck was unremarkable. The patient did not have any skin lesions on his body or limbs.
Fig. 1 Endoscopic view showing chromoblastomycosis of the left middle turbinate.
An endoscopic biopsy of the lesion was performed. The histopathological examination findings revealed acute and chronic inflammatory cells, and several granulomatous inflammations. The latter consisted of multinucleated giant cells and macrophages containing thick-walled, yeast-like, brown ‘sclerotic bodies’. The findings were compatible with granulomatous inflammation due to chromoblastomycosis (Figures 2 and 3). Gremilius methenamine silver stain confirmed the fungal infection; however, we did not culture for a specific fungus.
Fig. 2 Photomicrograph showing granulomatous inflammation composed mainly of macrophages, a multinucleated giant cell, and some neutrophils and other inflammatory cells. The sclerotic cells of chromoblastomycosis (arrows) were found in the giant cell. (H&E; ×40)
Fig. 3 Photomicrograph showing sclerotic cells of chromoblastomycosis (arrow) within a multinucleated giant cell. (Gremilius methenamine silver; ×40)
The patient was managed conservatively with nasal alkaline douching as he was not keen on undergoing any surgical intervention at the time.
At the follow-up review five months later, the patient had no complaints and the lesion size had remained the same. Nevertheless, we plan to excise the lesion to prevent recurrence of epistaxis or an increase in lesion size.
Discussion
Chromoblastomycosis is a chronic infection of the skin and subcutaneous tissue caused by pigmented or dematiaceous fungi. It most commonly affects the lower limbs, but any part of the body can be affected following traumatic inoculation of the fungus into the skin by a thorn or splinter, for example.Reference López Martínez and Méndez Tovar1, Reference Minotto, Benardi, Mallmann, Edelweiss and Scroferneker3, Reference Estere and Queiroz-Telles7 Ours is an exceptionally rare case involving the mucosa of the left middle turbinate, for which our patient could not remember any trauma. This may suggest that the fungus can be inhaled and subsequently establish infection in the nose, like other fungal infections of the nose and paranasal sinuses, without any trauma to the mucosa. Cases of chromoblastomycosis involving the mucosa of the nasal septum and maxillary sinus are very rare.Reference Symmers8, Reference Yamamoto and Caselitz9
Other differential diagnoses of similar skin lesions include leishmaniasis, leprosy, cutaneous sarcoidosis, cutaneous tuberculosis and malignancies.Reference Ameen2, Reference Rasul, Hazarika, Sharma, Borua and Sen5 Chromoblastomycosis lesions are usually confined to skin and subcutaneous tissue, but may involve muscles and bones in immunocompromised individuals.Reference Ameen2 Some known complications are secondary infection, lymphoedema and elephantiasis, and malignant transformation into squamous cell carcinoma.Reference López Martínez and Méndez Tovar1, Reference Ameen2 Distant dissemination through lymphatic and haematogenous spread to vital organs, such as the lungs and brain, has also been reported.Reference López Martínez and Méndez Tovar1, Reference Ameen2 Diagnosis is achieved by direct microscopy (with 10 per cent potassium hydroxide preparation) of the biopsy sample taken from the lesion.Reference López Martínez and Méndez Tovar1, Reference Ameen2, Reference Rasul, Hazarika, Sharma, Borua and Sen5
• Chromoblastomycosis of nasal mucosa is extremely rare
• The fungus may cause infection following inhalation into the nasal cavity, without any trauma to mucosa
• As the progression of infection is very slow over many years, a small lesion may be managed conservatively with follow up
Treatment of chromoblastomycosis is challenging as it has a low cure rate but high relapse rate, and spontaneous resolution is rare; however, most cases progress very slowly over a number of years.Reference López Martínez and Méndez Tovar1, Reference Ameen2 A long course of chemotherapy, with antifungal treatment (itraconazole and terbinafine are most effective), for 6 to 12 months, is required.Reference Ameen2, Reference Zhang, Xi, Lu, Li, Xie and Zhang10 Other modes of treatment include surgical excision, laser excision and cryotherapy with liquid nitrogen.Reference Ameen2, Reference Estere and Queiroz-Telles7 Combined therapy with pulsed itraconazole and liquid nitrogen cryotherapy has also been described, with findings that suggest this therapy is cost effective and requires a shorter period of treatment.Reference Ranawaka, Amarasinghe and Hewage11
In conclusion, chromoblastomycosis of the nasal wall is very rare and can be misdiagnosed as other common granulomatous conditions. As the disease has very slow progression over many years, small lesions may be managed conservatively with follow up.
