A case of human Dirofilaria repens infection, causing an asymptomatic subcutaneous nodule.

We present a case of subcutaneous dirofilariasis, a vector-borne zoonotic disease, in a young woman from Austria. The diagnosis was confirmed by ultrasound and histology of the excised subcutaneous nodule. The parasite species was identified as Dirofilaria repens by polymerase chain reaction. We expect to see more cases of human dirofilariasis also due to climate change and associated increase of the spectrum of suitable mosquito vectors.

Reflectance confocal microscopy for the diagnosis of skin infections and infestations.

Reflectance confocal microscopy (RCM) is a noninvasive real-time imaging technique that has been widely used for the diagnosis of skin cancer. More recently, it has been reported as a useful tool for the diagnosis and management of several inflammatory and infectious skin disorders. This article provides an overview of the current available applications of RCM use in cutaneous infections and infestations. PubMed was used to search the following terms in various combinations: reflectance confocal microscopy, skin, hair, nail, infection, parasitosis, mycosis, virus, bacteria. All papers were accordingly reviewed. In most cutaneous infections or infestations, the main alterations are found in the epidermis and upper dermis, where the accuracy of confocal microscopy is nearly similar to that of histopathology. The high resolution of this technique allows the visualization of most skin parasites, fungi, and a few bacteria. Although viruses cannot be identified because of their small size, viral cytopathic effects can be observed on keratinocytes. In addition, RCM can be used to monitor the response to treatment, thereby reducing unnecessary treatments.

Parasitic Infections of the Skin and Subcutaneous Tissues.

A variety of arthropods, protozoa, and helminths infect the skin and subcutaneous tissues and may be identified by anatomic pathologists in standard cytology and histology preparations. The specific organisms seen vary greatly with the patient's exposure history, including travel to or residence in endemic countries. Arthropods are the most commonly encountered parasites in the skin and subcutaneous tissues and include Sarcoptes scabei, Demodex species, Tunga penetrans, and myiasis-causing fly larvae. Protozoal parasites such as Leishmania may also be common in some settings. Helminths are less often seen, and include round worms (eg, Dirofilaria spp.), tapeworms (eg, Taenia solium, Spirometra spp.), and flukes (eg, Schistosoma spp.). This review covers the epidemiologic and histopathologic features of common parasitic infections of the skin and subcutaneous tissues.

A Case of Cutaneous Myiasis Caused by Cordylobia anthropophaga Larvae in a Korean Traveler Returning from Central Africa.

The cutaneous myiasis has been rarely reported in the Republic of Korea. We intended to describe here a case of furuncular cutaneous myiasis caused by Cordylobia anthropophaga larvae in a Korean traveler returned from Central Africa. A patient, 55-year-old man, had traveled to Equatorial Guinea, in Central Africa for a month and just returned to Korea. Physical examinations showed 2 tender erythematous nodules with small central ulceration on the left buttock and thigh. During skin biopsy, 2 larvae came out from the lesion. C. anthropophaga was identified by paired mouth hooks (toothed, spade-like, oral hooklets) and 2 posterior spiracles, which lack a distinct chitinous rim. Although rarely described in Korea until now, cutaneous myiasis may be encountered more frequently with increasing international travel and exchange workers to tropical areas.

Disseminated Cutaneous Rhinosporidiosis.

A 41-year-old man from the state of Chhattisgarh, India, had a previous history of nasopharyngeal rhinosporidosis for 27 years, for which he had surgical intervention seven times, most recently endoscopically 2 months earlier. For the last 8 months, he had noticed skin lesions on the shoulders and forehead. Of interest was a history of bathing in ponds as a child. Examination revealed a soft, skin-colored, strawberry-shaped papule on the forehead (Figure 1A), a papule with a hemorrhagic crust on the left shoulder (Figure 1B), and a crusted friable plaque on the right shoulder (Figure 1C). Endoscopy revealed a 1 cm × 1 cm red polypoidal mass on the lateral wall of the nasopharynx. A diagnosis of disseminated cutaneous rhinosporidiosis with nasal-nasopharyngeal rhinosporidiosis was considered.

Subcutaneous dirofilariasis: a masquerade of a palisaded granulomatous dermatitis.

Dirofilaria species are roundworms responsible for "heartworm" in canines. On occasion, humans are an accidental host, resulting in pulmonary (Dirofilaria immitis) or extrapulmonary (Dirofilaria repens) manifestations. Of the extrapulmonary sites of involvement, subcutaneous involvement is particularly common. We report a case of a 49-year-old female who presented with an erythematous nodule on her shin, which closely resembled necrobiosis lipoidica on histopathologic examination. On closer examination, there were foci of necrosis that harbored segments of the nematode, diagnostic of dirofiliarisis. We present this case to highlight the histopathologic similarities and differences between palisaded necrobiotic conditions and this potentially underrecognized entity.

Parasitic outbreak of the copepod Balaenophilus manatorum in neonate loggerhead sea turtles (Caretta caretta) from a head-starting program.

BACKGROUND: Diseases associated to external parasitosis are scarcely reported in sea turtles. During the last decades several organism have been documented as a part of normal epibiont community connected to sea turtles. The copepod Balaenophilus manatorum has been cited as a part of epibiont fauna with some concern about its parasitic capacity. This study serves three purposes, i.e. (i) it sheds light on the type of life style that B. manatorum has developed with its hosts, particularly turtles; (ii) it makes a cautionary note of the potential health risks associated with B. manatorum in sea turtles under captivity conditions and in the wild, and (iii) it provides data on effective treatments against B. manatorum. RESULTS: We report for the first time a massive infestation of the copepod B. manatorum and subsequent acute mortality in a group of loggerhead sea turtle hatchlings. Four-month-old turtles from a head-starting program started exhibiting excitatory and fin rubbing behavior preceding an acute onset of lethargy, skin ulceration and death in some animals. All the individuals (n = 57) were affected by severe copepod load and presented different degrees of external macroscopic skin lesions. The ventral area of front flippers, axillar and pericloacal skin were mostly affected, and were the main parasite distribution regions. Copepods were also detected on plastron and carapace sutures. The gut contents of B. manatorum reacted positively for cytokeratin, indicating consumption of turtle skin. Severe ulcerative necrotic dermatitis and large amount of bacteria presence were the major histopathological findings. CONCLUSIONS: Individual fresh water immersion for 10 min and lufenuron administration (0.1 ppm) to the water system every 2 weeks proved effective for removing turtle parasites and to control re-infestation, respectively. The results from our study clearly indicated that B. manatorum individuals consume turtle skin. The pathological effects of this agent and the potential implications in sea turtle conservation and management are discussed.

Trichoscopic diagnosis of cutaneous Pelodera strongyloides infestation in a dog.

BACKGROUND: Pelodera strongyloides infestation has rarely been reported in dogs. It is a saprophytic free-living nematode, found in moist decaying organic matter, whose L3 larval stages occasionally can invade the skin of dogs and humans. Larvae penetrate the follicular infundibula causing an erythematous and pruritic dermatitis. The disease is usually diagnosed by deep skin scraping or histopathology, with large numbers of parasites readily identified in hair follicles. CASE REPORT: Pelodera strongyloides dermatitis was diagnosed in a six-year-old mixed breed dog presenting with alopecia, erythema and severe pruritus on the ventrum and limbs. The infestation was diagnosed by microscopic examination of plucked hair shafts and confirmed on microscopic examination of skin biopsies collected for histopathology. Only two of 10 deep skin scrapings gave positive findings. The nematode infestation was eradicated following two applications, 2 weeks apart, of a moxidectin/imidacloprid spot-on product. CONCLUSION AND CLINICAL IMPORTANCE: Skin scrapings are considered the diagnostic test of choice for P. strongyloides infestations. In this case, parasites were identified by hair trichograms more readily than by skin scrapings.

A rare case of cutaneous acanthamoebiasis in a renal transplant patient.

A 35-year-old woman receiving immunosuppressionfor renal transplantation presented with a onemonthhistory of tender skin nodules on herbilateral upper extremities. A skin biopsy revealedgranulomatous inflammation in the deep dermisand the subcutaneous fat with foci of necrosis.Within the foci of necrosis were large histiocytoidstructures with prominent nuclei. Periodic acid-Schiffstain revealed a round organism with a thick capsule,consistent with amoebal trophozoites. Testing withthe Center for Disease Control revealed the organismto be Acanthamoeba. Despite antimicrobial therapy,the patient continued to develop subcutaneousnodules that extended to the lower extremities andtrunk and ultimately extended to the bone, causingacanthamoebal osteomyelitis. Throughout thehospital course, the patient remained neurologicallyintact without evidence of central nervousinvolvement. A diagnosis of isolated disseminatedcutaneous acanthamoebiasis secondary to iatrogenicimmunosuppression was made. Historically, mostcases of granulomatous amoebic encephalitisand cutaneous acanthamoebiasis have occurredin patients with HIV/AIDS. However, with the useof newer and more effective immunosuppressiveregimens, both are occurring more frequently inthe setting of iatrogenic immunosuppression. Therare and isolated cutaneous nature of this patient'spresentation makes this case unique.

Centrofacial Balamuthiasis: case report of a rare cutaneous amebic infection.

Free-living amebae are ubiquitous in our environment, but rarely cause cutaneous infection. Balamuthia mandrillaris has a predilection for infecting skin of the central face. Infection may be restricted to the skin or associated with life-threatening central nervous system (CNS) involvement. We report a case of a 91-year-old woman, who presented with a non-healing red plaque over her right cheek. Several punch biopsies exhibited non-specific granulomatous inflammation without demonstrable fungi or mycobacteria in histochemical stains. She was treated empirically for granulomatous rosacea, but the lesion continued to progress. A larger incisional biopsy was performed in which amebae were observed in hematoxylin-eosin stained sections. These were retrospectively apparent in the prior punch biopsy specimens. Immunohistochemistry and polymerase chain reaction studies identified the organisms as Balamuthia mandrillaris. Cutaneous infection by B. mandrillaris is a rare condition that is sometimes complicated by life-threatening CNS involvement and which often evades timely diagnosis due to its rarity and nonspecific clinical manifestations. Moreover, these amebae are easily overlooked in histopathologic sections because of their small number and their resemblance to histiocytes. Dermatopathologists should be familiar with the histopathologic appearance of these organisms and include balamuthiasis and other amebic infections in the differential diagnosis of granulomatous dermatitis.

Tick Bite Alopecia: A Report and Review.

Tick bites can cause a number of local inflammatory reactions, which are often difficult to differentiate from those induced by other arthropod bites or stings. These include erythematous nodular or pustular lesions, erosive plaques, annular lesions of erythema chronicum migrans, and both scarring and nonscarring inflammatory alopecia. We report a case of nonscarring alopecia in a 21-year-old male who reported a recent history of tick bite to the scalp. The biopsy demonstrated a dense pseudolymphomatous inflammatory infiltrate with numerous eosinophils associated with hair follicle miniaturization and an elevated catagen-telogen count. Signs of external rubbing, including lichen simplex chronicus and the "hamburger sign", were also visualized and are indicative of the associated pruritus. To the authors' knowledge, this is the fifth report of nonscarring tick bite alopecia in the literature and the first in an adult patient. This text will review the classic clinical presentation, histologic findings, and proposed mechanism of tick bite alopecia.

Protozoal nodular dermatitis and panniculitis in a Rottweiler puppy caused by Caryospora bigenetica.

BACKGROUND: Caryospora bigenetica is an intracellular protozoan parasite in snakes and raptors (primary hosts) and rodents (secondary host). Experimental infection has been documented in mice, pigs and goats; natural infection in dogs is rare. OBJECTIVES: To describe the clinical presentation, histological features, treatment and outcome of a case of protozoal nodular dermatitis and panniculitis in a Rottweiler puppy caused by C. bigenetica. RESULTS: The puppy presented with generalized subcutaneous nodules measuring up to 2 cm in diameter. Histopathology revealed marked suppurative to pyogranulomatous dermatitis and panniculitis with intralesional protozoal organism. PCR and DNA sequencing confirmed infection with C. bigenetica. Treatment with a combination of oral trimethoprim-sulfamethoxazole (TMS), pyrimethamine and high-dose clindamycin (20 mg/kg twice daily) resulted in resolution of lesions in 6 weeks. Discontinuation of the treatment 2 weeks later was followed by a rapid relapse of skin lesions. Clindamycin and TMS were restarted and all lesions resolved within 2 weeks; TMS was discontinued 4 weeks later due to adverse effects. The lesions remained in remission for 2 months while the puppy received clindamycin monotherapy before a second relapse of skin lesions occurred. CONCLUSION AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first documentation of the treatment and outcome of C. bigenetica cutaneous infection in a dog. Although remission of clinical signs can be achieved with combination therapy of clindamycin and TMS, long-term management is challenging and relapses should be anticipated.

Emergence of cutaneous neosporosis in a dog receiving immunosuppressive therapy: molecular identification and management.

BACKGROUND: Neosporosis is a multisystemic disease caused by the intracellular protozoan Neospora caninum. In dogs the disease primarily affects the central nervous system. Canine cutaneous neosporosis is a rare condition often associated with old age or concurrent immunosuppressive treatments for different underlying conditions. ANIMALS: A 10-year-old female spayed golden retriever dog affected by primary immune-mediated myelofibrosis and treated with immunosuppressive therapies for 6 weeks that developed severe cutaneous lesions. METHODS: Definitive diagnosis was based on several investigation techniques including serology (immunoblotting), immunohistochemistry (IHC), species-specific conventional and real-time PCR, and DNA sequencing. RESULTS: Remission of cutaneous neosporosis was obtained with the administration of clindamycin while the concurrent immunosuppressive therapy was maintained to manage the underlying primary condition. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge this is the first report of species-specific PCR and DNA sequencing used as diagnostic methods for canine cutaneous neosporosis emerging in a dog receiving immunosuppressive therapy.

Infections by Renibacterium salmoninarum and Nanophyetus salmincola Chapin are associated with reduced growth of juvenile Chinook salmon, Oncorhynchus tshawytscha (Walbaum), in the Northeast Pacific Ocean.

We examined 1454 juvenile Chinook salmon, Oncorhynchus tshawytscha (Walbaum), captured in nearshore waters off the coasts of Washington and Oregon (USA) from 1999 to 2004 for infection by Renibacterium salmoninarum, Nanophyetus salmincola Chapin and skin metacercariae. The prevalence and intensities for each of these infections were established for both yearling and subyearling Chinook salmon. Two metrics of salmon growth, weight residuals and plasma levels of insulin-like growth factor-1, were determined for salmon infected with these pathogens/parasites, both individually and in combination, with uninfected fish used for comparison. Yearling Chinook salmon infected with R. salmoninarum had significantly reduced weight residuals. Chinook salmon infected with skin metacercariae alone did not have significantly reduced growth metrics. Dual infections were not associated with significantly more severe effects on the growth metrics than single infections; the number of triple infections was very low and precluded statistical comparison. Overall, these data suggest that infections by these organisms can be associated with reduced juvenile Chinook salmon growth. Because growth in the first year at sea has been linked to survival for some stocks of Chinook salmon, the infections may therefore play a role in regulating these populations in the Northeast Pacific Ocean.

Balamuthia mandrillaris in South America: an emerging potential hidden pathogen in Perú.

Balamuthia mandrillaris is a free living amoeba that can be isolated from soil. It is an emerging pathogen causing skin lesions as well as CNS involvement with a fatal outcome if untreated. Further, infections can sometimes can also appear in peripheral areas such as extremities (usually knee), or trunk. Moreover, it often progresses to an infiltrative lesion that occasionally becomes ulcerated. In countries like Peru, a skin lesion will precede other symptoms. This primary cutaneous lesion can be present for weeks or even months. However, the appearance of neurological disease predicts a poor prognosis. Diagnosis requires a high level of suspicion.

Do not forget the stool examination!-cutaneous and gastrointestinal manifestations of Blastocystis sp. infection.

Blastocystis sp. is one of the most common parasites in the human intestinal tract. This infection commonly is accompanied by diarrhoea and abdominal pain, but extraintestinal symptoms, such as skin lesions, may also accompany the disease. In this study, our aim was to assess the frequency, clinical symptoms and skin manifestations of confirmed positive Blastocystis sp. infections. Data of 80 patients with confirmed positive Blastocystis sp. infections were assessed retrospectively. The average age of the patients was 46.3 years of age (with a range between 13 and 85 years of age). The number of female patients was higher than the number of males (48 vs. 32; 60 vs. 40%). Gastrointestinal and dermatological symptoms and the results of routine biochemical and haematological blood tests of enrolled patients were collected and analyzed. The skin manifestations were analyzed using the data available (including descriptions, photos and histologies). We discovered that 11.25% of our enrolled patients exhibited skin manifestations associated to Blastocystis sp., mainly on the females. The occurrence of Blastocystis sp. was 6% in symptomatic patients who required medical attendance in the time period between 2005 and 2013. Of the 80 patients, 73.75% indicated that they had gastrointestinal symptoms: 40 patients complained of abdominal pain and 17 with blood in their stool, while other symptoms, such as meteorism (15 subjects), weigh loss (8 subjects), perianal pain or itching (6 subjects), passing stool with mucus (5 subjects), vomiting (2 subjects) and fever (2 subjects) were less frequent. The prevalence of abdominal pain in the cohort without skin lesions was higher compared to those patients with skin problems (p = 0.007). The mean value of C-reactive protein showed elevated levels, but eosinophils were within a normal range. In addition, we did not find significant difference in eosinophilia between patients with vs. without skin manifestations. Thus, we suggest that eosinophilia is not an obligatory laboratory finding in protozoon infections, such as Blastocystis sp. In the light of our results, we suggest a stool parasite examination for patients with skin lesions of unknown origin.

[Results of studies of human dirofilariasis in Russia].

Human dirofilariasis is a pressing health problem in Russia. By 2014, there have been as many as 850 Dirofilaria repens-infested people living in 42 subjects of the Russian Federation. One of the favorable factors for circulation and spread of invasion is a temperature of above +20-24 degrees C; when the latter is maintained during at least 20 days there may be 1.-1.5 circulations of invasion in the carrier and a 2.8-fold increase in transmission intensity. The border ofa dirofilariasis area with a temperate climate is southward to 58 degrees N in European Russia and West Siberia and southward to 50 degrees N in the Far East. The conditions in the human body have been found to be more favorable for the development of Dirofilaria than considered before and allow the helminth to achieve sexual maturity and to propagate. If man has microfilaremia, he may be a source of invasion. It is necessary to examine venous blood by the enrichment method and, if possible, polymerase chain reaction and enzyme immunoassay, which make it possible to establish a diagnosis in occult invasion and to identify a pathogen species.

Cutaneous gnathostomiasis: report of 6 cases with emphasis on histopathological demonstration of the larva.

BACKGROUND: Cutaneous gnathostomiasis is an emerging food-borne parasitic zoonosis. Histopathological demonstration of the larva on random biopsy specimen of erythematous plaques is infrequent because of its migrating nature. OBJECTIVE: We sought to determine whether medical treatment with albendazole or ivermectin increases the diagnostic yield of skin biopsy specimen. METHODS: A retrospective chart review was conducted in a private dermatology practice in Lima, Peru. Cases with a clinical diagnosis of nodular migratory panniculitis and pathological diagnosis of eosinophilic panniculitis or gnathostomiasis were reviewed. Only cases with definitive diagnosis confirmed by histopathology or parasite isolation were included in the study. RESULTS: A definitive diagnosis of gnathostomiasis was rendered in 6 of 55 reviewed cases. Histopathological or gross identification of the nematode's larva was made obtaining a biopsy specimen of papules or pseudofuruncles that developed after oral antiparasitic treatment. LIMITATIONS: This is a retrospective case series study and no serologic testing was available. CONCLUSION: Biopsy of a papule or pseudofuruncle subsequent to oral treatment increases the likelihood of demonstrating the larva on skin biopsy specimen, which allows definitive diagnosis and may have therapeutic benefit.