Primary cutaneous coccidioidomycosis: first imported case in north India.

Coccidioidomycosis is a fungal disease found only in the Western Hemisphere. In recent years, the incidence of the disease has increased in California and Arizona, which may be partially due to the rapid immigration of previously unexposed persons from states outside the endemic areas. The disease in the nonendemic areas is usually imported. Determining a history of exposure is critical for performing the diagnosis of coccidioidomycosis in these cases. Histopathological examination is the key to the diagnosis when fungal culture and molecular studies are not available. We hereby report an imported case of cutaneous coccidioidomycosis, which to the best of our knowledge is the first case report from North India.

What was known?

Coccidioidomycosis is a disease of endemic areas of Western Hemisphere. Very few cases from nonendemic areas have been reported.

Introduction

Coccidioidomycosis (commonly known as Valley fever or San Joaquin fever) is an endemic disease caused by the dimorphic soil dwelling fungus Coccidioides. The rare cases in nonendemic areas are mostly imported, and suspected based on the evidence of endemic exposure.[1] Most human infections are caused by Coccidioides immitis. Coccidioidomycosis may vary from a clinically inapparent infection to a severe or fatal mycosis.[2] We herein present the detailed description of an imported isolated cutaneous coccidioidomycosis, which to our knowledge is the first such case from North India.

Case Report

A 62-year-old man presented to our dermatology clinic with complaints of multiple discharging sinuses over the neck and right axillary region of 2 months duration. He gave history of gradual progression in the lesion with minimal discharge. He denied any associated trauma, fever, weight loss, or history of tuberculosis. On specific questioning the patient revealed that he is a retired teacher by profession and stays in California for the past 10 years and visits India once a year.

On examination there were multiple discharging sinuses on the anterior aspect of neck and right axilla. Mild erythema around the sinus opening and minimal serosanguinous discharge from the sinus was noticed [Figure 1]. Systemic examination was normal.

Figure 1

Multiple discharging sinus in axilla and note the erythema around the opening and serosanguinous discharge

Tests results including complete blood count, erythrocyte sedimentation rate, urine routine, renal function test, liver function test, viral markers (HIV, HBsAg, HCV), mantoux test, and chest X-ray were within normal limits. Clinical possibilities of scrofuloderma and hidradenitis suppurutiva were considered and tissue was sent for histopathological examination.

The skin biopsy showed normal epidermis and dermis had chronic inflammatory infiltrate comprising of lymphocytes and plasma cells along with noncaseating granulomas. A few thick-walled large round structures were seen, which were present both inside the granulomas and in the surrounding stroma. Periodic Acid Schiff (PAS) stain highlighted these structures and showed globular sporangia with some of them possessing sporangiospores diagnostic of coccidioidomycosis [Figures 2 and 3].

Figure 2

Spherules of coccidioidomycosis within the epithelioid cell granulomas (H and E stain, ×400)

Figure 3

Spherules of coccidioidomycosis with sporangia within it highlighted by PAS stain (×400)

Cultures were not performed. The patient was started on fluconazole 400 mg once a day for 4 weeks. (Azole group of drugs such as fluconazole and others are recommended in the literature and standard textbooks as treatment of choice in dose 400 mg once to twice a day for 4-6 weeks.) Symptomatic relief in the form of healing of discharging sinuses was noticed.

Discussion

Coccidioidomycosis is caused by the dimorphic soil-dwelling fungus Coccidioides immitis. The fungus is endemic to a geographically delineated area within the United States known as the Lower Sonoran Life Zone.[2] The disease transmission is either through direct contact or indirect exposure to contaminated secretions. The incubation period for primary pulmonary or cutaneous coccidioidomycosis is usually 1-3 weeks, however, disseminated disease or chronic pulmonary coccidioidomycosis can occur months or years after the initial infection.[3]

The life zone of Coccidioides spp. is in the hot deserts of the southwestern United States: Texas, Arizona, Nevada, New Mexico, and much of central and southern California.[34] The reason for the disease not being prevalent in India might be attributed to the lack of optimum conditions such as the semi-arid climate and the flora for the fungus to thrive.[5] Exposure to the soil containing spores is the only risk factor for acquiring the disease. High inoculum exposures during windstorms, digging, farming, and construction are more likely to result in symptomatic disease. Our patient denied a history of any such activity.[12]

After being exposed to the infecting agent, about 60% of the individuals remain asymptomatic, 40% develop “valley fever,” which is a self-limiting flu-like illness, 5% of the people develop pulmonary disease, and only 0.5% people develop a disseminated disease involving skin, bones, and central nervous system. Isolated cutaneous involvement is rare.[2]

In tissue culture, C. immitis is identified by large globular sporangia, which contain sporangiospores or endospores. The spores enlarge to form spherules and rupture of the spherules leads to the release of endospores, which elicit a suppurative reaction as evidenced in our case. Intact sporangia usually elicit a granulomatous reaction of histiocytes, epithelioid cells and giant cells of the foreign body or of Langhan's type. The present case highlighted the characteristic findings.[3]

Histopathological examination on the lesion tissues is considered to be more valuable and easier to perform as culture and molecular diagnostic modalities are not routinely available in laboratories in the non-epidemic regions. Identification of endospore-containing spherules differing in diameter from 20 to 200 μm without budding under microscopy is definitely diagnostic of coccidioidomycosis. Commonly used histological stains, such as the hematoxylin and eosin and PAS distinguish typical morphological structures of coccidioidomycosis spherules and can also differentiate it from budding yeast forms of Blastomyces, Histoplasma, Cryptococcus, or Candida.[3678]

In our patient, the characteristic history and revealing morphological features on histology confirmed the diagnosis for coccidioidomycosis.

Coccidioidomycosis is extremely rare in India with only three cases reported so far[910] [Table 1]. With an increase in international travel some travellers may acquire infection indigenous to the regions travelled that may pose baffling clinical problems. This report emphasizes the importance of a proper travel history and histopathological examination to detect unusual and exotic infections.

Table 1

Review of imported cases reported as coccidioidomycosis in India

What is new?

This is the fourth imported case of coccidioidomycosis in India and is first from North India.