Primary cutaneous cryptococcosis and a surprise finding in a chronically immunosuppressed patient

Received 16 June 2014 Accepted 15 August 2014 Infectious Diseases Research Laboratory, 4 Department of Internal Medicine, University General Hospital ‘‘ATTIKON’’, School of Medicine, National and Kapodistrian University of Athens, Greece 2 Department of Pathology, University General Hospital ‘‘ATTIKON’’, School of Medicine, National and Kapodistrian University of Athens, Greece 2nd Department of Dermatology, University General Hospital ‘‘ATTIKON’’, School of Medicine, National and Kapodistrian University of Athens, Greece Department of Medical Microbiology, Canisius-Wilhelmina Ziekenhuis (CWZ) Hospital, Nijmegen, The Netherlands 2 Department of Urology, School of Medicine, National and Kapodistrian University of Athens, Greece


Introduction
The basidiomycetous yeast genus Cryptococcus contains approximately 100 species but only two of them are well known for their ability to cause disease in humans and animals (Fonseca et al., 2011).Cryptococcus neoformans, with a worldwide occurrence, can be differentiated into two varieties named grubii (serotype A) and neoformans (serotype D).Its sibling, Cryptococcus gattii (serotypes B and C), is more restricted to tropical, subtropical and Mediterranean climate zones.C. neoformans can be isolated from decaying wood, fruits, vegetables, hay and dust, but a major way of spread is through bird droppings, especially those of pigeons.Entry of Cryptococcus into the human body occurs through the respiratory system, but also though skin abrasions and injuries (Chayakulkeeree & Perfect, 2006).In immunocompromised individuals, such as those with long-term corticosteroid use, transplant recipients, patients with haematological malignancies and particularly those with human immunodeficiency virus infection (Lu et al., 2007;Jasch et al., 2008;Singh et al., 2008;Park et al., 2009;Reisfeld-Zadok et al., 2009), Cryptococcus can cause severe and life-threatening meningoencephalitis, pulmonary infection with cryptococcomas and skin lesions through haematogenous spread.The skin is the third most common organ involved in cryptococcosis; secondary cutaneous cryptococcosis affects about 15 % of patients with disseminated disease and 5 % of patients with meningitis (Chayakulkeeree & Perfect, 2006).Primary cutaneous cryptococcosis (PCC) is a rare form of cryptococcosis considered a distinct clinical entity (Christianson et al., 2003;Neuville et al., 2003) affecting both immunocompetent and immunocompromised individuals through direct inoculation of the yeasts, after injury with contaminated material.Here we present a patient with clinically, microbiologically and histologically diagnosed PCC, with a history of myasthenia gravis under corticosteroid treatment.

Case report
A 61-year-old Caucasian male was referred in March 2013 to the outpatient clinic of our hospital for cutaneous lesions on the dorsum of his left middle finger.These lesions consisted of a large skin ulceration and two small satellite lesions.The large ulceration was deep, round and painless with a grimy crater and heaped-up red and irregular borders, overlying the first interphalangeal joint (Fig. 1a).One of the satellite lesions was a firm, erythematous and oedematous nodular eruption with an initiating ulceration area on the top, and was located on the distal phalange of the same finger.The other was an erythematous and oedematous papule overlying the knuckle of the middle finger.These lesions had developed gradually over an 8-month course.They began as cellulitis, subsequently becoming oedematous with overlying redness simulating lymphocutaneous disease, before the main lesion ulcerated.Physical examination did not reveal any proximal epitrochleal or axillary lymphadenopathy or fever.
During the 8-month period, the patient had received various antimicrobial regimens including b-lactams and clindamycin without any clinical improvement.He had a known history of myasthenia gravis, which was diagnosed at the age of 28 years and was being treated with pyridostigmine and 25 mg prednisolone daily.He did not report any other co-morbidities that could predispose to his condition.He lived in a rural area in southern Greece and, the patient recalled that he had a plant thorn injury of his left hand while gardening at home, before the lesions appeared.He did not report any travel outside Greece or his area of residence.

Investigations
A swab sample was taken and cultured on Sabouraud glucose agar (SGA).After 2 days of incubation at 30 u C, the culture became positive for a mucoid yeast morphologically suggestive of Cryptococcus.Blood samples were taken for laboratory investigation.All routine biochemical parameters (glucose, creatinine, bilirubin, aspartate transaminase, alanine aminotransferase, c-glutamyl transpeptidase, alkaline phosphatase, lactate dehydrogenase and C-reactive protein were within normal range.A blood count showed white blood cells at 9.9610 9 l 21 with 79 % neutrophils.A biopsy of the core lesion was performed for histological and microbiological examination.A direct KOH preparation was negative for fungi, but Cryptococcuslike colonies grew on SGA.

Diagnosis
The cultured yeast was molecularly characterized using amplified fragment length polymorphism (AFLP) fingerprinting according to Arsic Arsenijevic et al. (2014), which showed that the isolate fell within the genotype Histology showed a diffuse inflammatory infiltrate in the dermis, consisting of lymphocytes, plasma cells and histiocytes lacking granulomas or multinuclear giant cells.Periodic acid-Schiff staining revealed yeasts surrounded by a clear 'halo', features consistent with Cryptococcus spp.(Fig. 1b).Blood cultures were negative.An X-ray of the hand showed no bone involvement.The cryptoccocal antigen in serum performed by latex agglutination (Pastorex Crypto Plus; Bio-Rad) was positive at a 1:32 dilution.A computed tomography (CT) scan showed no pulmonary involvement; nevertheless, it simultaneously disclosed the presence of a right kidney lesion extending to the perirenal adipose tissue and posterior aspect of Gerota's fascia.Subsequently, a right nephrectomy was performed; histological examination showed clear cell renal cell carcinoma Fuhrman nuclear grade 2, with accompanying perirenal fat expansion.

Treatment
The patient was started with 200 mg fluconazole twice daily, prednisolone was reduced to 2.5 mg daily, pyridostigmine remained unchanged, and he was referred to the urology department.He underwent surgical removal of the mass 5 weeks thereafter, at which point he stopped the antifungal therapy on his own.Five months later, he was started on anti-tumour treatment with sunitinib, a receptor protein-tyrosine kinase inhibitor.

Outcome and follow-up
The patient was followed up at frequent intervals for 8 weeks from the initiation of the antifungal treatment, with his lesion exhibiting obvious signs of granulation tissue and general improvement (Fig. 2).The cryptoccocal serum antigen titre was reduced to 1 : 16.A year later, the lesions were completely healed and there were no signs of systemic infection, despite the early cessation of antifungal treatment.He tolerated the anti-tumour therapy well and further follow-up examinations were recommended.

Discussion
PCC was first described in the 1950s; but its existence as a distinct clinical entity has long been disputed.Instead, it was considered by some to be a manifestation of disseminated disease in immunocompromised individuals (Sarosi et al., 1971;Noble & Fajardo, 1972;Hay, 1985;Perfect & Seaworth, 1985;Kwon-Chung et al., 2000).New evidence, however, has changed this concept (Ng & Loo, 1993;Christianson et al., 2003;Neuville et al., 2003;Baumgarten et al, 2004;Lafleur et al, 2004;Pietras et al., 2010).In fact, Neuville and co-workers ( 2003) defined criteria that characterize PCC and can be used for the clinical diagnosis.The clinical and laboratory findings of the case presented here are consistent with this clinical entity, namely lesions confined to a limited body area, history of prior injury (in this case, a plant thorn), exposure to a contaminated source (probably the plant thorn), a rural area of living, no systemic signs, no extracutaneous sites positive for Cryptococcus and a favourable outcome.Moreover, the isolate involved belonged to serotype D, mostly associated with PCC (Neuville et al., 2003).A skin ulcer developing chronically may be the result of a cutaneous infection or primary cutaneous cancer (Ingleton et al., 1998).The differential diagnosis includes infection with common bacteria such as Staphylococcus aureus, Streptococcus pyogenes, atypical mycobacteria such as M. marinum, M. avium and M. intracellulare, Nocardia spp., parasites of the genus Leishmania and fungi.Coexistence of an infectious agent with Kaposi's sarcoma has also been described (Pietras et al., 2010).
Fungal genera usually associated with the described clinical presentation are Blastomyces, Coccidioidomyces, Cryptococcus, Histoplasma, Sporothrix and Paracoccidioidomyces. Except for Crypococcus, these fungi presuppose residence or visit in endemic areas, such as certain areas in North and Latin America.
The history of multiple antimicrobial regimens without any result along with the history of cellular immunosuppression of the patient was more suggestive of a fungal or mycobacterial infection (Christianson et al. 2003;Lafleur et al. 2004).In this case report, we present a rare case of a composite lesion (papule, ulcer and lymphocutaneous pattern) of PCC.This is suggestive of the wide spectrum of lesions Cryptococcus can cause (papules, cellulitis, whitlow, lymphocutaneous morphology, ulcer, pyoderma gangrenosum, chancre, discoid lupus erythematosus-like), even in the same patient (Miura et al., 1971;Ng & Loo, 1993;Christianson et al., 2003;Neuville et al., 2003;Baumgarten et al., 2004;Lafleur et al., 2004;Jasch et al., 2008;Posada et al., 2009).The combination of a confined lesion in immunosuppressed patients, along with cellulitis, often leads to a delayed diagnosis of PCC and of recurrent trials of unsuccessful therapeutic regimens (Christianson et al., 2003;Fallah et al., 2011).In such cases, early culture, before empirical administration of antimicrobials, is of great importance.
As in the majority of the cases reported, patients with either PCC or systemic cryptococcosis have a cellular immunity defect.Corticosteroid use and post-transplant immune status have been identified as the most common causes, but other causes such as human immunodeficiency virus infection, malignancies or even a transient decrease in lymphocytes have also been identified (Ng & Loo, 1993;Christianson et al., 2003;Neuville et al., 2003;Baumgarten et al., 2004;Lafleur et al., 2004).However, there are reports of PCC in patients with intact immunity, a fact supporting the concept of a distinct clinical entity (Bellosta et al., 1999;Lacaz Cda et al., 2002;Revenga et al., 2002).The significance of a positive blood antigen test in the setting of an apparent PCC is uncertain.It may indicate a serious skin infection, cryptoccocal meningoencephalitis or an early manifestation of disseminated disease (Neuville et al., 2003;Baumgarten et al., 2004;Lafleur et al., 2004).A positive antigen, however, should not exclude PCC (Hafner et al., 2005).In this patient, the positive antigen titre, although low, posed a serious question whether the lesion was confined to the finger or was an early indicator of a systemic cryptoccocal infection.Cutaneous lesions can be the only symptom and an early marker of disseminated disease.On the other hand, it is not unusual for PCC patients to have secondary antigenaemia due to severe local infection (Neuville et al., 2003).Whether the natural history and risk of dissemination of PCC is the same in patients with positive or negative serum latex agglutination remains a question (Christianson et al., 2003).Therefore, it was extremely important for this patient to have regular follow-up examinations during a 10-month period to exclude the possibility of developing systemic or disseminated disease (Neuville et al., 2003;Ng & Loo, 1993;Sarosi et al., 1971).In the case of persistent antigen titre, an unapparent colonization site should be excluded (Hafner et al., 2005).
Considering the fact that our patient did not exhibit any systemic involvement such as lymphadenopathy or fever, as well as the fact that the chest CT scan was negative for pulmonary disease, a lumbar puncture and a CT scan of the head were not considered necessary.The incidental finding of a mass on the right kidney, in conjunction with the positive blood antigen, was highly suggestive of renal cryptococcoma.Surprisingly, the histological investigation revealed clear cell renal cell carcinoma.There have been laboratory data on the kidney carcinoma ability to depress cellular immunity function secondary to its by-products (Das et al., 2008a, b;Biswas et al., 2009).As a result, two factors of cellular immunity dysfunction were identified in this patient; an iatrogenic one and a neoplastic one.In most reports of either PCC or skin manifestations of systemic cryptococcosis where only one immunosuppressive factor was identified, histological findings were consistent with granulomatous inflammation (Ng & Loo, 1993;Baumgarten et al., 2004;Neuville et al., 2003;Hafner et al., 2005).This case is remarkable in that no evidence of systemic or disseminated disease was detected, despite the coexistence of two factors of cellular immunity dysfunction.
The Infectious Diseases Society of America guidelines for cryptococcal disease do not refer to confined skin disease in immunocompromised patients (Perfect et al., 2010).Because of his medical history of chronic iatrogenic immunosuppression, the patient was prescribed 200 mg fluconazole twice daily, indefinitely.However, he stopped this treatment on his own after only 5 weeks, fortunately without consequences.There are reports stating discontinuation of corticosteroid treatment during cryptococcal infections (Anderson et al., 1992).We preferred not to do so, considering a possible flare of myasthenia gravis (Lafleur et al., 2004).Follow-up at 2, 5 and 8 weeks showed obvious granulation tissue in the base of the ulcer and epitheliopoiesis of the lesion, a sign of clinical improvement.

Fig. 1 .
Fig. 1.(a) Lesions before treatment.(b) Periodic acid-Schiff staining of the core lesion biopsy revealing yeasts surrounded by a clear 'halo' and a diffuse inflammatory infiltrate in the dermis.Magnification 640.