Immunostaining of Visceral Leishmaniasis Caused byLeishmania infantumUsing Monoclonal Antibody (19–11) to theLeishmaniaHomologue of Receptors for Activated C-Kinase

Cryptococcemia presenting as an opportunistic infection due to chronic visceral leishmaniasis

We present a case of visceral leishmaniasis (VL) in a previously immunocompetent patient. At the time of presentation, he was co-infected with Cryptococcus neoformans. This case demonstrates how infectious diseases besides human immunodeficiency virus can lead to immunosuppression for patients, placing them at risk of opportunistic infections.

Histopathological characteristics of cutaneous lesions caused by Leishmania Viannia panamensis in Panama

Cutaneous leishmaniasis (CL) is an endemic disease in the Republic of Panama, caused by Leishmania (Viannia) parasites, whose most common clinical manifestation is the presence of ulcerated lesions on the skin. These lesions usually present a chronic inflammatory reaction, sometimes granulomatous, with the presence of lymphocytes, plasma cells and macrophages. This study describes the histopathological characteristics found in the skin lesions of patients with CL caused by Leishmania (V.) panamensis in Panama. We analyzed 49 skin biopsy samples from patients with clinical suspicion of CL, by molecular tests (PCR for subgenus Viannia and HSP-70) and by Hematoxylin-Eosin staining. Samples were characterized at the species level by PCR-HSP-70/RFLP. From the 49 samples studied, 46 (94%) were positive by PCR and were characterized as Leishmania (V.) panamensis. Of these, 48% were positive by Hematoxylin-Eosin staining with alterations being observed both, in the epidermis (85%) and in the dermis (100%) of skin biopsies. The inflammatory infiltrate was characterized according to histopathological patterns: lymphohistiocytic (50%), lymphoplasmacytic (61%) and granulomatous (46%) infiltration, being the combination of these patterns frequently found. The predominant histopathological characteristics observed in CL lesions caused by L. (V.) panamensis in Panama were: an intense inflammatory reaction in the dermis with a combination of lymphohistiocytic, lymphoplasmacytic and granulomatous presentation patterns and the presence of ulcers, acanthosis, exocytosis and spongiosis in the epidermis.

Pathology of infectious diseases: what does the future hold?

The demand for expertise in pathology for the diagnosis of infectious diseases (ID) is continually growing, due to an increase in ID in immunocompromised patients and in the (re)-emergence of common and uncommon diseases, including tropical infections and infections with newly identified microbes. The microbiology laboratory plays a crucial role in diagnosing infections, identifying the responsible infectious agents and establishing sensitivity of pathogens to drug therapy. Pathology, however, is the only way to correlate the presence of an infectious agent with the reaction it evokes at cell and tissue level. For pathologists working in the field of ID pathology, it is essential to dispose of competence in cell and tissue pathology as well as in microbiology. Expertise in ID includes understanding of taxonomy and classification of pathogens as well as morphological criteria supporting their identification. Moreover, ID pathologists must master the methods used to detect pathogens in fixed cell and tissue samples, notably immunohistochemistry, in situ hybridization and the polymerase chain reaction. Paradoxically, the increasing frequency of lesions caused by pathogens and diagnosed in a pathology laboratory appears to be paralleled by a gradual loss of expertise of pathologists in the field of infectious and tropical diseases. We contend that this may be due at least in part to the continuously increasing number of samples of tumor tissue pathologists deal with and the rapidly expanding number of tissue based biomarkers with predictive value for new anti-cancer therapies. In this review, we highlight current and future issues pertaining to ID pathology, in order to increase awareness of its importance for surgical and molecular pathology. The intention is to contribute to the development of best practice in ID pathology.

[What place and what future for the pathology of infectious and tropical diseases in France?]

The management of tissues and cellular samples by the pathologists in the infectious and tropical diseases pathology field in 2014 needs a strong knowledge of both morphological and molecular domains which includes the good control: (i) of the taxonomy of infectious and tropical diseases pathology leading to the pathogens identification and (ii) of the ancillary methods which can be used in fixed samples in order to detect or better identify these pathogens. There is a recent paradox in France concerning the frequency of infectious diseases to be diagnosed in pathology laboratories and the progressive loss of pathologist's expertise in this domain. Different reasons could explain this statement including the omnipresence of the tumour lesions to be managed in a pathology laboratory as well as the recent constraints associated with the different biomarkers that are mandatory to be detected by immunohistochemistry and/or by molecular biology. Even if the microbiologists play a pivotal role for identifying the different pathogens as well as for the assessment of their sensitivity to the anti-microbial drugs, a large number of infectious diseases can be diagnosed only on fixed tissue and/or cells by the pathologists. The purpose of this review is to describe the current and future issues of infectious and tropical diseases diagnoses in pathology laboratories, in particular in France.

Clinical, histopathologic, and cytologic diagnosis of mucosal leishmaniasis and literature review

CONTEXT

Mucosal leishmaniasis (ML) is a rare disease in the world, even in endemic areas such as Iran. Clinical, histologic, or cytologic assessment may help in the diagnosis of ML.

OBJECTIVE

To describe clinical, histologic, and cytologic findings in ML.

DESIGN

Review of our files showed 11 patients diagnosed with ML, of whom 7 patients had oral lesions, 1 of whom was a known patient with oral leishmaniasis with recurrence of oral lesions; 2 had laryngeal lesions; and 3 had nasal lesions. One case of laryngeal leishmaniasis was a recurrence of prior oral lesions. Cytologic smears were prepared by scraping the lesions with a scalpel or cytobrush. Histology on the biopsies was done for 7 patients. In 2 patients with nasal lesions, exfoliative cytology was made by washing the nasal cavity. Smears were both air dried and fixed in alcohol and stained.

RESULTS

Cytologic findings showed free Leishman-Donovan bodies, intrahistiocytic Leishman-Donovan bodies, atypical organisms, granuloma, acute and chronic inflammatory cells, histiocytes, multinucleated giant cells, mast cells, binucleated histiocytes (Reed-Sternberg-like cells), and plasma cells. In 6 of the patients, biopsy was inconclusive and in subsequent cytology the organism was detected. In 3 cases, findings from clinical and cytologic examinations were suggestive for leishmaniasis; however, with response to treatment, the diagnosis was confirmed. In 5 patients a malignant tumor was suspected because of clinical or histologic findings, but cytology helped to diagnose leishmaniasis.

CONCLUSIONS

Clinically or histologically, ML can be mistaken for benign and malignant lesions. Scraping or exfoliative cytology is an easy, reliable, and cost-effective method for diagnosing ML. Thus, clinical, histologic, and cytologic features together may help in ML diagnosis.

Usefulness of oral cytopathology in the diagnosis of infectious diseases

In recent years, the incidence of oral opportunistic infections has increased, partly due to the widespread implementation of organ and bone marrow transplantation and the increase in the prevalence of human immunodeficiency virus (HIV) infection. Cytology can be used as a rapid, inexpensive and simple routine procedure in diagnosing infectious diseases of the mouth. Moreover, ancillary methods can be applied to cytological samples, increasing the specificity and sensitivity for the diagnosis of infectious diseases. This review describes the cytopathological features of the main viral, fungal, bacterial and parasitic infections of the mouth. Cytological techniques of specimen collection, identification of infectious agents by cytomorphological approaches and ancillary methods, and diagnostic pitfalls will be discussed.

[Pathologic findings and main aetiologies of rhinosinusal infections]

A large variety of infectious diseases may involve the rhinosinusal tract. They include bacterial, viral, fungal, and parasite infections. These infections can induce an acute and/or a chronic inflammatory reaction. They can develop both in immunocompetent or in immunodeficient patients. Clinically, the consequences of these infections are variable, but a few of them have to be rapidly diagnosed for an immediate specific treatment. This article describes the pathologic features of a variety of infectious diseases that surgical pathologists may encounter in analysis of biopsy specimens taken from the rhinosinusal tract.

Microscopic evaluation of renal changes in experimental canine visceral leishmaniosis after chemo- and immunotherapy

Visceral Leishmania (VL) with diverse clinical manifestation is prevalent and remains a major public health problem in Iran. This study was performed in Ahwaz, Khozestan province southwest to increase immune system and to reduce of the renal lesions. Treatment of dogs with visceral leishmaniosis is basically the same as the treatment of human. However, cure is not usually achieved, leaving the sacrifice of animal as the only feasible choice. The goal of this work was to test the therapeutic efficacy of N-methyl glutamic antimoate (glucnime), Mycobacterium vaccae adjuvant (SRL 172), alone and in association with L. major promastigote and the latter compound in association to glucantime, in dog with visceral leishmaniasis. In this trial 18, mixed bred dogs with different ages, receiving amastigte promastigote of L. infantum intravenously were used. They were monitored for 6 months. Serologic assays (Elisa, Dot and IFAT) were performed on blood samples of each animal. The animals were divided into six groups, each having 3 dogs: Group 1: receiving 100 mg kg(-1) day(-1) Glucantime for 30 days, IM. Group 2: Receiving 3 mg dog(-1) (0.1 mL) of Mycobacterium vaccae adjuvant suspension intradermaly. Group 3: receiving L. major promastigote plus M. vaccae adjuvant each of them 0.1 mL intradermaly by one month intervals for 3 months. Group 4: receiving Glucantime in association L. major promastigote plus M. vaccae adjuvant with previous doses. Group 5: Receiving no treatment. Group 6: was control group with no infection and treatment. In microscopic evaluation following lesions have been shown in kidney: Chronic, interstitial nephritis, sever glomerulosclerosis, membranoproliferative glomerulonephritis and also non suppurative nephritis were the lesions in 5 groups. The prescription of Mycobacterium vaccae adjurant was able to reduce the number of parasites in the macrophages of liver and spleen in this round of treatment.

Application of immunohistochemistry to infections

CONTEXT

Pathologists play an important role in the diagnosis or exclusion of infectious diseases. Traditionally, the diagnosis of infectious diseases rely on serologic assays and cultures. Serologic results may be difficult to interpret in the setting of immunosuppression, fresh tissue is not always available for culture, and culture of fastidious pathogens can be difficult and may take weeks or months to yield a result. Although some microorganisms or their cytopathic effects may be readily identifiable on routine and/or histochemical stains, often these changes are not specific or are sparse in the sample evaluated. In these cases, additional immunohistochemical stains are often needed to establish the diagnosis of infection.

OBJECTIVE

To review the current value and limitations of the use of immunohistochemistry in the diagnosis of infectious diseases in formalin-fixed tissue samples.

DATA SOURCES

Literature in Medline and the authors' own experience.

CONCLUSIONS

Immunohistochemistry has proven to be a useful tool in the diagnosis of infectious diseases in tissue samples. Immunohistochemistry is especially useful in the identification of microorganisms that are present in low numbers, stain poorly, are fastidious to grow, are noncultivable, or exhibit an atypical morphology. Finally, it is important to remember that there may be widespread occurrence of common antigens among bacteria and pathogenic fungi and both monoclonal and polyclonal antibodies must be tested for possible cross-reactivity with other organisms.

Diagnosis of canine visceral leishmaniasis: biotechnological advances

Human visceral leishmaniasis (HVL) is endemic in the tropical and sub-tropical regions of Africa, Asia, the Mediterranean, Southern Europe and South and Central America, with approximately 500,000 new cases reported annually. As dogs are considered to be the major reservoirs for HVL, the accurate diagnosis of disease in these animals is important. Diagnosis of canine visceral leishmaniasis (CVL) is performed mainly by direct parasitological methods that can yield false-negative results, either because of the very low number of Leishmania spp. organisms in clinical samples (bone marrow and lymph nodes) or because morphological identification is difficult. In addition, these methods are invasive. Conventional serological techniques are limited by cross-reactivity with other parasitic diseases and because several technical procedures have not been standardised. The development of polymerase chain reaction based approaches and immunoassays based on the use of recombinant antigens aimed at improving the sensitivity and specificity of CVL diagnosis is discussed.

Detection of Leishmania infantum kinetoplast DNA in laryngeal tissue from an immunocompetent patient

Mucosal leishmaniasis of the upper respiratory tract is usually associated with the visceral form or is found in immunosuppressed individuals. This report presents a case of isolated mucosal leishmaniasis in an immunocompetent patient, whose diagnosis mainly rested on histology and positive polymerase chain reaction result for Leishmania donovani in the laryngeal tissue. A 59-year-old man, who never lived outside Italy, showed a subglottic mucosal polypoid-like lesion. The typical morphological picture and positive polymerase chain reaction result for L donovani by DNA extracted from laryngeal biopsy specimens allowed the diagnosis of mucosal leishmaniasis. Specific amphotericin B therapy was started, resulting in clinical and endoscopic improvement. Increased knowledge about the histological and molecular tissue analysis of Leishmania enhances the diagnostic testing for mucosal leishmaniasis, as primary mucosal leishmaniasis may occur in both immunosuppresed and immunocompetent patients who travel to or reside in areas endemic for Leishmania.