We applied the polymerase chain reaction to detection of the pathogenic protozoan Toxoplasma gondii based on our identification of a 35-fold-repetitive gene (the BI gene) as a target. Using this procedure, we were able to amplify and detect the DNA of a single organism directly from a crude cell lysate. This level of sensitivity also allowed us to detect the BI gene from purified DNA samples containing as few as 10 parasites in the presence of 100,000 human leukocytes. This is representative of the maximal cellular infiltration (105/ml) in 1 mi of cerebrospinal fluid obtained from patients with toxoplasmic encephalitis. The BJ gene is present and conserved in all six T. gondii strains tested to date, including two isolates from patients with acquired immunodeficiency syndrome. No signal was detected by using this assay and DNAs from a variety of other organisms, including several which might be found in the central nervous system of an immunocompromised host. This combination of sensitivity and specificity should make detection of the BJ gene based on polymerase chain reaction amplification a very useful method for diagnosis of toxoplasmosis both in immunocompromised hosts and in congenitally infected fetuses.

Telogen effluvium (TE) is one of the most common causes of diffuse nonscarring hair loss. In its acute form, it generates a lot of anxiety in the patient, which can be significantly allayed with a confident diagnosis. In its more chronic form, however, the hair loss may go unnoticed for long periods of time. Here in, the dermatologist's role in differentiating it from the more common patterned hair loss is significant. Differentiating TE from other causes of diffuse nonscarring hair loss can indeed be a daunting task and TE is often used as a waste basket diagnosis. A number of factors have been implicated in the causation of TE, however, clear evidence in their support is lacking. The role of stress as a causative factor as well as the result of hair loss needs to be adequately understood. This review aims at summarizing our current level of knowledge with respect to this very common cause of hair loss. An attempt is made to help the readers reliably differentiate TE from other causes of diffuse nonscarring hair loss. The possible causative factors, pathogenetic mechanisms, clinical presentation, and possible treatment options are discussed.

Nail involvement in psoriasis is common, and the severity of it does not always parallel the intensity of cutaneous disease. We created a consensus group, of which the aim was to provide practical recommendations for the treatment of nail psoriasis in patients without skin psoriasis or with mild skin lesions with no indication for a systemic treatment. This collaborative process was conducted by an international panel of dermatologists with special expertise in nail disorders, using formal consensus methods. During this process, the panel strived to establish an agreement regarding the definition of nail psoriasis, the severity of nail psoriasis, and treatment response. Treatment recommendations are provided

Histopathological examination of nails is a valuable diagnostic aid, especially in the absence of skin lesions. Examination of the PAS-stained sections is necessary before making a histological diagnosis of nail psoriasis because onychomycosis and psoriasis may show similar histology.

Onychomycosis (OM) is the commonest disorder affecting the nail unit. The fact that it affects 3-26% people worldwide goes to show that it is a significant health problem. The prevalence of OM has been reported to be increasing over the years. Although, we know much about various predisposing factors, we are yet unclear about its exact pathogenesis. The peculiarities of the nail unit with respect to its structure and its immune mechanisms make OM an adversary, which once established is difficult to eradicate. There have been many recent advances in our understanding of the pathogenesis of OM and our methods of diagnosing it. The increasingly valuable role of histopathology; refinements in its technique; PCR techniques; Optical coherence tomography and advances in spectrometric techniques have been reported. The present review is aimed at discussing the newer advances in our understanding of the pathogenesis of various clinical types of OM apart from the newer and exciting techniques of diagnosing it.

Infection of pregnant women with Toxoplasma gondii places the developing fetus at risk for congenital infection. We report a prospective study of 43 documented cases of acute maternal Toxoplasma infections acquired during gestation in which the polymerase chain reaction (PCR) was evaluated for diagnosis of fetal infection and compared with the current standard methods. On the basis of direct lysis of pelleted amniotic fluid cells followed by amplification of a gene sequence specific for T. gondii, PCR correctly identified the presence of T. gondii in five of five samples of amniotic fluid from four proven cases of congenital infection. PCR also detected three of five positive cases from a nonprospective group. The two diagnostic methods of comparable speed, detection of specific immunoglobulin M from fetal blood and inoculation of amniotic fluid into tissue culture, correctly identified only 3 and 4 of the 10 positive samples, respectively. The considerably more time-consuming methods of mouse inoculation of amniotic fluid and fetal blood both detected 7 of 10 positive samples. There were no false-positive diagnoses by any of the methods. Therefore, detection of T. gondii by PCR appears to be the most promising method for prenatal diagnosis of congenital Toxoplasma infection, since it is both extremely rapid and highly sensitive.

Onychomycosis is a fungal nail infection caused by dermatophytes, nondermatophyte molds, and yeasts. This difficult‐to‐treat chronic infection has a tendency to relapse despite treatment. This paper aims to offer a global perspective on onychomycosis management from expert physicians from around the world. Overall, the majority of experts surveyed used systemic, topical, and combination treatments approved in their countries and monitored patients based on the product insert or government recommendations. Although the basics of treating onychomycosis were similar between countries, slight differences in onychomycosis management between countries were found. These differences were mainly due to different approaches to adjunctive therapy, rating the severity of disease and use of prophylaxis treatment. A global perspective on the treatment of onychomycosis provides a framework of success for the committed clinician with appreciation of how onychomycosis is managed worldwide.

In the present study, clinical morphology or KOH findings were not found to be clearly or exclusively predictive of the species involved. There was a fair degree of overlap in the clinical or microscopic patterns produced by the fungal species. Mixed patterns were observed both on clinical examination as well as on KOH examination. However, none of the specimens grew more than one fungal species.