Primary cryptococcal cellulitis caused by Cryptococcus neoformans var. gattii in an immunocompetent host

A global view on fungal infections in humans and animals: opportunistic infections and microsporidioses

After cardiovascular diseases, infectious diseases are the second most common cause of death worldwide. Although these infections are caused mainly by viruses or bacteria, a systematically growing prevalence of human and animal opportunistic fungal infections is noticeable worldwide. More attention is being paid to this problem, especially due to the growing frequency of recalcitrant and recurrent mycoses. The latter are classically divided into superficial, which are the most common type, subcutaneous, and systemic. This work discusses opportunistic fungal pathogens without proven horizontal transmission between different animal species including humans and microsporidia as spore-forming unicellular parasites related to fungi; however, with a yet undetermined taxonomic position. The review also mentions aetiological agents, risk factors, epidemiology, geographical distribution, and finally symptoms characteristic for individual disease entities. This paper provides insight into fungal infections from a global perspective and simultaneously draws attention to emerging pathogens, whose prevalence is continuously increasing. Finally, this work also takes into consideration the correct nomenclature of fungal disease entities and the importance of secondary metabolites in the pathogenesis of fungal infections.

Cryptococcus gattii infections

Understanding of the taxonomy and phylogeny of Cryptococcus gattii has been advanced by modern molecular techniques. C. gattii probably diverged from Cryptococcus neoformans between 16 million and 160 million years ago, depending on the dating methods applied, and maintains diversity by recombining in nature. South America is the likely source of the virulent C. gattii VGII molecular types that have emerged in North America. C. gattii shares major virulence determinants with C. neoformans, although genomic and transcriptomic studies revealed that despite similar genomes, the VGIIa and VGIIb subtypes employ very different transcriptional circuits and manifest differences in virulence phenotypes. Preliminary evidence suggests that C. gattii VGII causes severe lung disease and death without dissemination, whereas C. neoformans disseminates readily to the central nervous system (CNS) and causes death from meningoencephalitis. Overall, currently available data indicate that the C. gattii VGI, VGII, and VGIII molecular types more commonly affect nonimmunocompromised hosts, in contrast to VGIV. New, rapid, cheap diagnostic tests and imaging modalities are assisting early diagnosis and enabling better outcomes of cerebral cryptococcosis. Complications of CNS infection include increased intracranial pressure, severe neurological sequelae, and development of immune reconstitution syndrome, although the mortality rate is low. C. gattii VGII isolates may exhibit higher fluconazole MICs than other genotypes. Optimal therapeutic regimens are yet to be determined; in most cases, initial therapy with amphotericin B and 5-flucytosine is recommended.

Primary cutaneous cryptococcosis treated with debridement and fluconazole monotherapy in an immunosuppressed patient: a case report and review of the literature

Cryptococcus neoformans is an opportunistic yeast present in the environment. Practitioners are familiar with the presentation and management of the most common manifestation of cryptococcal infection, meningoencephalitis, in patients with AIDS or other conditions of immunocompromise. There is less awareness, however, of uncommon presentations where experience rather than evidence guides therapy. We report a case of primary cutaneous cryptococcosis (PCC) in a patient who had been immunosuppressed by chronic high-dose corticosteroid for the treatment of severe asthma. This case highlights the importance of early recognition of aggressive cellulitis that fails standard empiric antibiotic treatment in an immunocompromised patient. It also demonstrates successful treatment of PCC with a multispecialty approach including local debridement and fluconazole monotherapy.

Primary cutaneous cryptococcosis in an immunocompetent patient due to Cryptococcus gattii molecular type VGI in Brazil: a case report and review of literature

Primary Cutaneous Cryptococcosis is an uncommon infection caused by the yeast Cryptococcus neoformans and C. gattii. Few case reports are available in the literature describing in detail primary cutaneous cryptococcosis due to C. gattii in immunocompetent patients. Herein, we present a case of a 68-year-old immunocompetent male patient with erythematous nodular lesions on the right forearm due to C. gattii mating-type α and molecular type VGI. The virulence factors test was performed for capsule diameter, melanin production and phospholipase activity. In vitro fluconazole testing showed the sensitivity profile of this clinical isolate. In addition, a review of the literature on this subject was carried out and verified that this is the first reported case of VGI in the south-east region of Brazil.

Primary cutaneous cryptococcosis caused by Cryptococcus gattii in an immunocompetent host

This paper presents the case of a 75-year-old Brazilian man who developed inflammatory skin lesions with nodules and ulcerations on the right forearm after an injury caused by handling barbed-wire and Eucalyptus spp. logs. Histopathological assessment of the lesions showed granulomatous processes with yeasts similar to Cryptococcus spp. Tissue fragments yielded yeasts when cultured that were identified as Cryptococcus gattii VGII through biochemical reactions and URA5-RFLP genotype. No evidence of systemic involvement or any underlying immunosuppressive diseases were identified, which supported the diagnosis of primary cutaneous cryptococcosis. After 5 months on therapy with high fluconazole doses, the skin lesions had fully healed.

Cutaneous Cryptococccosis Due to Cryptococcus gattii in Immunocompetent Hosts: Case Report and Review

Cutaneous cryptococcosis caused by C. gattii, in immunocompent patients is a rare manifestation of disease, and may be one of the first manifestations of disseminated cryptococcosis. We report a case of disseminated cryptococcosis caused by Cryptococcus gattii presenting as cutaneous lesions in an immunocompetent patient. Previously to our report, only five cases of cutaneous involvement by Cryptococcus gattii in immunocompetent patients have been reported in the literature. Risk factors for C. gattii infection included exposure to the eucalypt reservoirs in tropical and subtropical areas. Skin involvement corresponded to the disseminated form of cryptococcosis in the majority of patients, and commonly affected the face and neck with different morphologies including papules, pustules, plaques, ulcers, subcutaneous masses, cellulitis or acneiform lesions. Due to the severity of this infection and the life threatening condition that it represents, clinicians must be aware that cutaneous involvement may be one of the first manifestations of disseminated cryptococcosis caused by C. gattii especially in patients living and coming from endemic areas.

Fine-needle aspiration diagnosis of primary cutaneous cryptococcosis in an immunocompetent patient: a case report

We report a case of a primary cutaneous cryptococcosis (PCC) in immunocompetent man diagnosed by fine-needle aspiration (FNA) and confirmed by special stains and culture study. The patient presented with a 2-wk history of two separate skin nodules over the forehead and the left lumbar region. FNA smears revealed a necrotizing suppurative granulomatous inflammation with numerous yeasts of Cryptococcus surrounded by clear halos, which were present within multinucleated giant cells and in the intercellular spaces. This was confirmed subsequently by special stains and a culture of the aspirated material. This case report reemphasizes the role of FNA as a useful modality in the early diagnosis of cutaneous cryptococcosis, especially in clinically unsuspected cases.

Primary cutaneous cryptococcal cellulitis secondary to insect bite in an immunosupressed patient after liver transplantation

Cutaneous cryptococcosis is usually a manifestation of disseminated disease, especially in immunosuppressed patients. Primary cutaneous cryptococcosis has also been described in some patients without evidence of systemic disease. Distinguishing between primary and secondary cutaneous cryptococcosis may be difficult as patients can be asymptomatic or cutaneous lesions may precede systemic involvement by some months. Features supporting primary disease are a history of cutaneous inoculation, and solitary superficial lesions on uncovered parts of the body. We present a liver transplant patient with cutaneous cryptococcal cellulitis subsequent to an insect bite, without systemic involvement and with excellent response to treatment with amphotericin B for 15 days and surgical debridement plus oral fluconazole for 3 months. In immunosupressed patients with cellulitis a cryptococcal infection must be excluded. If cutaneous cryptococcosis is diagnosed, systemic evaluation and prompt lengthy treatment are required.

Two cases of cutaneous cryptococcosis

We report two cases of cutaneous cryptococcosis in male patients without underlying disease. Case 1 had a granulomatous mass on his right neck, gradually enlarging for 3 months. After the mass was debrided surgically in a hospital, the incision wound gradually developed into a severe ulceration. Mycological examination revealed Cryptococcus neoformans infection. It was significant that histopathology of both pre-surgery granuloma and post-surgery ulceration revealed thick-walled spores with thick capsule. Chest X-ray revealed a shadow in the left lower lung. After treatment with amphotec for 21 days, the lesion healed. Case 2 had an approximately 2 x 2 cm solitary dull nodule on his right thigh, which had been present for 8 months. Mycological examination confirmed that the lesion was caused by C. neoformans. The patient's ratio of peripheral blood CD4(+) cell was slightly reduced. After 14 days of treatment with oral fluconazole, followed by oral itraconazole for 2 months, mycological and clinical cure were achieved. The two isolates were identified as C. neoformans var. gattii serotype C and C. neoformans var. grubii serotype A.

Cutaneous cryptococcosis in a diabetic renal transplant recipient

A diabetic renal transplant recipient with cellulitis caused by Cryptococcus neoformans, serotype A, is described. The diagnosis was based on the demonstration of capsulated, budding yeast cells in the aspirated material and tissue from the cellulitic lesion and isolation of the aetiological agent in culture. The isolate formed well-developed capsules in the brain tissue of experimentally infected mice and produced cherry-brown colonies on niger seed medium. The patient's serum was positive for cryptococcal antigen (titre 1 : 4) with no other evidence of systemic infection. He was successfully treated with AmBisome, followed by fluconazole, resulting in the complete resolution of cellulitis and disappearance of the cryptococcal antigen. This report underscores the fact that patients with cutaneous cryptococcosis should be thoroughly evaluated, as it may be the first manifestation of a systemic disease. Prompt diagnosis and treatment are important to improve survival.

Primary cutaneous cryptococcosis: a distinct clinical entity

Cryptococcus neoformans is an encapsulated yeast responsible for disseminated meningitis in immunocompromised hosts. Controversies persist on the existence of primary cutaneous cryptococcosis (PCC) versus cutaneous cryptococcosis being only secondary to hematogenous dissemination. Thus, we reviewed cryptococcosis cases associated with skin lesions reported in the French National Registry. Patients with PCC (n=28) differed significantly from those with secondary cutaneous cryptococcosis (n=80) or other forms of the disease (n=1866) by living area (mostly rural), age (older), ratio of men to women (approximately 1:1), and the lack of underlying disease. Evidence of PCC included the absence of dissemination and, predominantly, a solitary skin lesion on unclothed areas presenting as a whitlow or phlegmon, a history of skin injury, participation in outdoor activities, or exposure to bird droppings, and isolation of C. neoformans serotype D. Therefore, PCC is a distinct epidemiological and clinical entity with a favorable prognosis even for immunocompromised hosts.

Primary cutaneous cryptococcosis due to Cryptococcus neoformans var. gattii serotype B, in an immunocompetent patient

The authors report a male patient, a seller with no detected immunosuppression, with an extensive ulcerated skin lesion localized on the left forearm, caused by Cryptococcus neoformans var. gattii serotype B. Oral treatment with fluconazole was successful. A review of the literature showed the rarity of this localization in HIV-negative patients. In contrast, skin lesions frequently occurs in HIV-positive patients, with Cryptococcus neoformans var. neoformans serotype A predominating as the etiological agent. In this paper, the pathogenicity of C. neoformans to skin lesions in patients immunocompromised or not, is discussed, showing the efficacy of fluconazole for the treatment of these processes.

Prospective use of RFLP analysis on amplified Cryptococcus neoformans URA5 gene sequences for rapid identification of varieties and serotypes in clinical samples

Clinical isolates of Cryptococcus neoformans, whole blood, cerebrospinal fluid, bronchoalveolar lavage fluid from patients with positive cryptococcal antigen latex-agglutination test, and spiked clinical material from healthy individuals, were tested by polymerase chain reaction (PCR) with primers amplifying C. neoformans URA5 gene sequences. To test compatibility of different DNA extraction protocols with the PCR-restriction fragment length polymorphism (RFLP) assay, a commercial DNA extraction kit (XTRAX; Gull Laboratories, UT, USA) was used alongside with the hexadecyltrimethylammonium bromide (CTAB) method on spiked biological fluids. Both methods extracted DNA from spiked clinical samples containing C. neoformans (8 +/- 2 cells ml(-1)) and generated amplification products suitable for restriction enzyme analysis. Alu I digestion differentiated the two varieties of C. neoformans. Three distinct RFLP patterns were obtained upon restriction with MspI corresponding to serotypes A, AD and B, C and D. URA5 PCR followed by RFLP analysis, coupled with a sensitive in-house or commercially available DNA extraction method from clinical samples, could be successfully incorporated into rapid routine diagnostic strategies. It could also provide an expeditious tool for epidemiology-based population genetics studies.