皮肤是猫整体健康的指标：感染性疾病的皮肤临床表现-（4）真菌及相关皮肤病

王帆

SKIN AS A MARKER OF GENERAL FELINE HEALTH

皮肤是猫整体健康的指标

Cutaneous manifestations of infectious disease

感染性疾病的皮肤临床表现

作者：Katherine Backel and Christine Cain
翻译：何梦婷   校对：王帆、刘欣

Fungi – and associated cutaneous disease

真菌及相关皮肤病
This review focuses on systemic fungal disease. Similar to atypical bacterial disease, systemic fungal disease often causes non- healing wounds, nodules and draining tracts. Associated inflammation is typically pyogranulomatous to granulomatous. Clinical presentations can be similar and may require histopathologic or microbiologic diagnosis. Dermatophytosis will not be discussed in this context but is the most common cutaneous fungal infection in cats.
本文就全身性真菌病进行综述。与非典型细菌病相似，全身性真菌病常导致伤口不愈合、结节和瘘道。相关的炎症通常为化脓性肉芽肿到肉芽肿。临床表现可能相似，可能需要组织病理学或微生物学诊断。皮肤癣菌病是猫最常见的皮肤真菌感染。

Cryptococcus and Aspergillus species

隐球菌和曲霉属
Cryptococcus species are dimorphic basidiomycetous fungi and the cause of the most common systemic mycosis of cats. There are at least 19 species described; of these, Cryptococcus neoformans and Cryptococcus gattii cause the majority of disease. Infection typically occurs through inhalation of spores from environmental sources.C neoformans is found in soil contaminated with pigeon excrement or decaying plant material. C gattii is found ubiquitously in the environment.
隐球菌是两型担子菌属真菌，是猫最常见的全身性霉菌病。至少有19种被描述；其中，新生隐球菌和gattii隐球菌引起大多数疾病。感染通常是通过吸入环境来源的孢子而发生的。在被鸽粪或腐烂的植物物质污染的土壤中发现了新生隐球菌。gattii隐球菌在环境中普遍存在。


Affected cats are typically young adults with access to the outdoors. However, approximately 25% of affected cats in the US are reported to be indoor-only. After inhalation, spores within the nasal cavity spread through the bloodstream to other tissues or ascend to the central nervous system through the cribriform plate. Cats can present with nasopharyngeal, central nervous system, ocular, cutaneous and/or systemic disease. While nasal cavity disease is most common (occur- ring in 40–90% of cases), cutaneous signs are reported in approximately half of cases, with the majority having signs localized to the nasal planum or bridge of the nose. Classically, single or multiple fluctuant to firm nodules present on the bridge of the nose, which may ulcerate or develop draining tracts (Figure 5a). Similar cutaneous lesions may present elsewhere as well. Sino-nasal/sino-orbital aspergillosis has been reported uncommonly, but with similar clinical signs, and may be included as a differential especially when facial deformation is noted. Affected patients commonly present with nasal discharge and sneezing. Exophthalmos and paranasal swelling is seen frequently in patients with sino-orbital disease, and draining tracts have been reported in patients with sinonasal disease.
患猫通常是能够接触到户外的年轻猫。然而，大约25%的受影响的猫在美国被报告为仅室内生活。吸入后，鼻腔内的孢子通过血流扩散到其他组织或通过筛板上升到中枢神经系统。猫可出现鼻咽、中枢神经系统、眼部、皮肤和/或全身疾病。虽然鼻腔疾病是最常见的（发生环在40 - 90%的情况下），皮肤症状报告在大约一半的情况下，大多数病变局限在鼻面或鼻梁。典型的是，鼻梁上有一个或多个波动到坚硬的结节，可能溃疡或形成瘘道（图5a）。类似的皮肤病变也可能出现在其他地方。中国鼻曲霉菌病和眼眶曲霉菌病的报道并不多见，但临床症状相似，特别是在面部变形时，可作为一种鉴别。患猫通常有鼻分泌物和喷嚏。在眼眶疾病的患猫中，眼球突出和鼻腔肿胀是常见的，而在鼻腔疾病的病例中，也有瘘道的报告。

Diagnosis can be made by identifying the organism in cytologic or tissue samples. Cryptococci are non-staining pleomorphic yeast-like organisms, 4–15 μm in diameter. They show narrow-based budding and are surrounded by a refractory capsule (Figure 5b). In biopsy samples, these organisms can be identified using special stains (PAS, GMS or Fontana-Masson). Confirmatory culture should be performed using biopsy samples.Latex agglutination tests for capsular antigen in serum can be used to  identify affected cats and monitor response to therapy. Infected cats typically have high titers, though titers can vary greatly between patients. Cryptococcosis should, therefore, not be ruled out based on low or negative titers, which may occur in some patients with primary ocular or CNS disease.
诊断可以通过看到细胞学或组织样本中的微生物进行鉴别。隐球菌是不着染多形性酵母样微生物，直径4-15μm。它们呈窄基出芽，被一个耐高温包囊包围（图5b）。在活组织检查样本中，这些微生物可以用特殊的染色剂（PAS、GMS或氨银染色法）来识别。应使用活组织检查样本进行诊断性培养。血清中荚膜抗原的乳胶凝集试验可用于识别患猫和监测治疗反应。受感染的猫通常具有高滴度，但滴度在不同的患猫之间可能有很大的差异，因此，不应根据低滴度或阴性滴度来排除隐球菌病，这可能发生在一些原发性眼部或中枢神经系统疾病的患猫身上。

Aspergillosis is typically diagnosed by identification of Aspergillus organisms on cytologic or histologic examination. Samples may be obtained using fine-needle aspiration or biopsy of the lesion. These findings must be confirmed by growth of the fungi in culture.
曲霉菌病通常是通过在细胞学或组织学检查中发现曲霉菌来确诊的。可通过细针抽吸或病变活检获得样本。这些发现必须通过培养中真菌的生长来证实。

Suspicion of blastomycosis and histoplasmosis should increase in patients presenting with cutaneous lesions and other systemic signs.
在出现皮肤病变和其他全身症状的患猫中，应高度怀疑芽生菌病和组织胞浆菌病。

Blastomyces and Histoplasma species

芽生菌和组织胞浆菌
Blastomyces dermatitidis is a dimorphic fungus found as a soil contaminant in endemic areas (Southeastern USA, around the Great Lakes, and Ohio and Mississippi river valleys). Although disease is more common in dogs, infections are occasionally reported in cats from endemic areas. Respiratory, ocular and cutaneous signs are found most commonly, although neurologic signs, including mentation changes, ataxia and circling, are present in up to 41% of affected cats. Dermatologic lesions are nodules with or without draining tracts, and are most commonly reported on the head, limbs or trunk.
皮肤芽生菌是一种二型真菌，在流行地区（美国东南部，五大湖周围，俄亥俄州和密西西比河流域）作为土壤污染物被发现。虽然这种疾病在犬身上更为常见，但在流行地区的猫身上偶尔也会报告感染。虽然呼吸、眼部和皮肤症状最常见，但多达41%的猫出现神经系统症状，包括精神改变、共济失调和转圈。皮肤病变是指结节伴有或没有瘘道，最常见于头部、四肢或躯干。

Histoplasma capsulatum is a dimorphic fungus found in nitrogen-rich soil (especially that contaminated by bat or bird excrement). It has been reported on almost all continents, but is endemic in the Midwestern and Southern United States. Histoplasmosis is more commonly reported in cats than blastomycosis.Cats most frequently present with respiratory (40%) and ocular signs (25%). The skin is infrequently affected but cutaneous nodules can occur.
组织胞浆菌是一种存在于富氮土壤（特别是被蝙蝠或鸟粪污染的土壤）中的二型真菌。几乎在所有大陆都有报道，但在美国中西部和南部是地方病。组织胞浆菌病比芽生菌病更常见于猫，猫最常出现呼吸（40%）和眼部症状（25%）。皮肤很少发病，但也可能发生皮肤结节。

Suspicion of blastomycosis and histoplasmosis should increase in patients presenting with cutaneous lesions and other systemic signs. The organisms may be detected on cytology or histopathology. Histoplasma species are often abundant in macrophages and are small (2–4 μm) round or oval bodies with a clear halo (Figure 6). Blastomycetes are thick walled, broad-based budding yeasts approximately 8–12 μm in diameter. In biopsy samples, organisms are best found using periodic-acid-Schiff (PAS) or Gomori’s methenamine silver (GMS) stain. Culture should only be performed in reference laboratories with appropriate facilities as the mycelial form in culture poses a risk for human infection. Antibody and antigen serum and urine testing has been utilized in cases of histoplasmosis and may be useful for monitoring clinical progression. Similarly, a urine antigen test is available and useful for diagnosis and monitoring of blastomycosis.However, since there may be cross-reactivity between systemic mycoses, these results should be interpreted carefully.
在出现皮肤病变和其他全身症状的患猫中，应高度怀疑芽生菌病和组织胞浆菌病。可以在细胞学或组织病理学上发现这些微生物。组织胞浆菌通常在巨噬细胞中大量存在，是小的（2-4μm）圆形或椭圆形体，具有清晰的光晕（图6）。芽生菌是厚壁、宽基芽殖酵母，直径约8～12μm。在活组织检查样本中，最好使用过碘酸希夫反应（PAS）或哥氏亚甲胺银染色（GMS）染色来发现微生物。培养只能在有适当设施的参考实验室进行，因为培养中的菌丝体形式会对人类感染造成风险。抗体、抗原、血清和尿液检测已被用于组织胞浆菌病的病例，可能有助于监测临床进展。同样，尿液抗原检测也可用于芽生菌病的诊断和监测。但是，由于全身性真菌病之间可能存在交叉反应，这些结果应该仔细解释。

Sporothrix species

孢子丝菌属
Sporotrichosis is caused by dimorphic saprophytic fungi within the Sporothrix schenckii complex (which include at least six species). Sporothrix species favor warm, humid climates and soil rich in decaying organic matter. Many mammals, including humans, are susceptible to infection. Cats are considered highly susceptible and may facilitate spread of the fungi in endemic areas. Large outbreaks in humans have been closely associated with disease in cats in Brazil. Sporothrix species infections occur worldwide, although the disease is considered endemic in Mexico, Brazil, Uruguay, Peru, China, Japan, India and South Africa. The disease is uncommon in the United States and Europe, although sporadic outbreaks have occurred.
孢子丝菌病是由申克孢子丝菌复合体内的二型腐生真菌引起的（至少包括6种）。孢子丝菌喜欢温暖潮湿的气候和富含腐朽有机质的土壤。包括人类在内的许多哺乳动物都易受感染。猫被认为是高度敏感的，可能有助于真菌在流行地区的传播。在巴西，人类的大规模爆发与猫的疾病密切相关。孢子囊菌感染在世界范围内发生，尽管该病被认为是墨西哥、巴西、乌拉圭、秘鲁、中国、日本、印度和南非特有的。这种疾病在美国和欧洲并不常见，尽管有零星的爆发。

Young adult intact male outdoor cats with a history of fighting are at the highest risk of developing sporotrichosis. Infection occurs when fungi are inoculated into skin wounds or through inhalation of spores. Affected cats may display a wide spectrum of signs, ranging from subclinical to severe. The overwhelming majority of patients show cutaneous lesions, which appear as small papules or nodules that may ulcerate and drain. Large areas of ulceration and necrosis that expose underlying muscle and bone may also be seen (Figure 7a). Lesions are most common on the head (especially the nose) and limbs, although some cases show mucosal involvement.Evidence of dissemination has been reported in 50–70% of cats; lungs, liver, spleen, kidneys, lymph nodes and/or testicles may be involved. Respiratory signs are the most common extracutaneous signs.
有打斗史的未成年雄性室外生活猫患孢子丝菌病的风险最高。当真菌被接种到皮肤伤口或通过吸入孢子而感染。患猫可能表现出广泛的症状，从亚临床到严重。绝大多数患猫皮肤病变表现为小丘疹或结节，可能有溃疡和瘘道。也可能有大面积的溃疡和坏死，暴露下的肌肉和骨骼（图7a）。病变最常见于头部（尤其是鼻子）和四肢，尽管有些病例有粘膜病变。50-70%的猫报告有传播迹象；可能累及肺、肝、脾、肾、淋巴结/或睾丸。呼吸道症状是最常见的皮肤病变以外的症状。

Diagnosis is based on identification of the organism in affected tissues or fungal culture. Cytologic analysis of exudate may reveal the presence of large numbers of organisms. Sporothrix species are cigar-shaped yeasts (4–6 x 5–9 μm) with narrow-based budding, often found within neutrophils and macrophages (Figure 7b).Organisms may be identified in close to 80% of cytologic samples and are typically abundant in biopsy samples as well (Figure 7c). Fungal culture (biopsy samples are preferred) can be performed to isolate the fungi. An ELISA for antibody against cell wall proteins, with a high sensitivity and specificity, has been developed but is not widely used.
诊断是基于发病组织或真菌培养物中发现出微生物。渗出液的细胞学分析可揭示大量微生物的存在。孢子丝菌属是雪茄状的酵母（4-6 x 5-9μm），具有窄基芽接，常见于中性粒细胞和巨噬细胞（图7b）。在接近80%的细胞学样本中可鉴定出有机体，并且通常在活检样本中也大量存在（图7c）。可进行真菌培养（首选活检样本）以分离真菌。酶联免疫吸附测定（ELISA）检测细胞壁蛋白抗体具有较高的灵敏度和特异性，但应用并不广泛。

Sporothrix species may be identified in close to 80% of cytologic samples from affected animals and are typically also abundant in biopsy samples.
孢子丝菌种类可在来自受影响动物的近80%的细胞学样本中确定，并且通常在活检样本中也大量存在。

Differentiating between systemic fungal infections

全身性真菌感染的鉴别诊断
Other systemic fungal disease, especially cryptococcosis, may present in a very similar manner to sporotrichosis.Differentials should be prioritized based on history,geographical location and presence of other systemic signs. Since systemic fungal diseases may be quickly and easily diagnosed based on microscopic appearance of the organisms,cytology of exudates should always be performed first. When no fungal organisms are present, other differentials including other causes of nodules and draining tracts should be considered (see box on page1155).
其他全身性真菌病，特别是隐球菌病，可能以与孢子丝菌病非常相似的方式出现。应根据病史、地理位置和其他全身性症状的存在来鉴别诊断。由于全身性真菌疾病可以快速和容易地根据显微镜下微生物的外观诊断，都应先进行分泌物细胞学检查。当没有真菌存在时，应考虑其他鉴别诊断，包括结节和瘘道的其他原因（见1155页方框）。

pc2230

小哥，来点图谱好吗？