Histopathology of Post Kala-azar Dermal Leishmaniasis

The various lesions seen in the clinical presentation of post kala-azar dermal leishmaniasis (PKDL) are reflected in the histopathology of the type of lesion biopsied. The cells that form the dermal infiltrate include lymphocytes, histiocytes, and plasma cells in varying proportions. The infiltrate, which is mild and confined to the superficial dermis in macular lesion becomes denser with the increasing severity of the lesion. Leishman–Donovan bodies (LDB) in general are rarely demonstrable in macules and somewhat infrequently in the rest, though at times they may be numerous; mucosal lesions offer a greater chance of visualizing LDB than biopsies from the skin. A characteristic histomorphology in nodules is prominent follicular plugging with a dense plasma cell-rich lymphohistiocytic dermal infiltrate that shows an abrupt cut-off in the lower dermis, an appearance highly suggestive of PKDL even in the absence of LDB. Russell bodies within plasma cells, vascular changes, and xanthoma-like hue have been seen in plaques from chronic PKDL. The histopathologic picture in some may also mimic that seen in tuberculoid and lepromatous leprosy, and other granulomatous dermatoses. In contrast to Indian PKDL, epithelioid cell granulomas with giant cells are more common in African PKDL, and vascular changes are rare though neuritis showing LDB has been described.

Validation of the diagnostic criteria for segmental vitiligo

Background

Segmental vitiligo has a different clinical course and prognosis as compared to nonsegmental vitiligo, which necessitates its correct diagnosis. It may be difficult to distinguish segmental vitiligo from the limited or focal types of nonsegmental vitiligo.

Objective

To validate the previously proposed diagnostic criteria for segmental vitiligo.

Methods

This was a cross-sectional validation study involving patients with limited vitiligo. The diagnostic criteria were used to classify vitiligo lesions as segmental or nonsegmental, and was compared with the experts' diagnosis, which was considered as the "gold standard".

Results

The study included 200 patients with 225 vitiligo lesions. As per the diagnostic criteria, 146 vitiligo lesions were classified as segmental and 79 as nonsegmental. The experts classified 147 vitiligo lesions as segmental and 39 as nonsegmental, while the diagnosis either was labeled "unsure" or could not be agreed upon for 39 lesions. As compared with the experts' opinions ("for sure" cases, n = 186), the sensitivity and specificity of the diagnostic criteria was 91.8% (95% confidence interval [CI]: 86.2%-95.7%) and 100% (95% CI: 91%-100%), respectively. The positive predictive value was 100% (95% CI: 97.3-100%), while the negative predictive value was 76.5% (95% CI: 62.5%-87.2%). There was a 93.5% agreement between the clinical criteria and experts' opinions (k = 0.83, P < 0.001).

Limitation

The diagnostic criteria were compared with the experts' opinion in the absence of an established diagnostic "gold standard".

Conclusions

The proposed diagnostic criteria for segmental vitiligo performed well, and can be used in clinical practice, as well as in research settings.

Follicular Becker's Nevus: A New Clinical Variant

Becker's nevus, also known as pigmented hairy epidermal nevus, is characteristically described as a unilateral, hairy, light to dark brown macule with sharply outlined but irregular border. The etiopathogenesis of Becker's nevus is still not clearly understood. Perifollicular pigmentation has been described earlier by some authors. But, Becker's nevus presenting exclusively with follicular lesions has not been described. We are reporting a series of patients of Becker's nevus with follicular lesions. The diagnosis in all the patients was made after clinicopathological correlation. Follicular epithelium may hold a significant role in the etiopathogenesis of Becker's nevus.

Lichenoid pseudovesicular papular eruption on nose: A papular facial dermatosis probably related to actinic lichen nitidus or micropapular polymorphous light eruption

Background

Facial papules are a feature of several clinical conditions and may present both diagnostic and therapeutic challenges.

Aim

To describe a grouped papular eruption on the nose and adjoining cheeks that has not been well characterized previously.

Materials and Methods

A series of consecutive patients with a papular eruption predominantly involving nose and cheeks were evaluated, treated and followed up prospectively at tertiary care centers. Demographic details, clinical features, histopathology and response to treatment were recorded.

Results

There were five men and six women (mean age 29.9 ± 6.9 years) who had disease for a mean duration of 17.3 ± 11.1 months. All patients presented with a predominantly asymptomatic eruption of monomorphic, pseudovesicular, grouped, skin colored to slightly erythematous papules prominently involving the tip of nose, nasal alae, philtrum and the adjoining cheeks. A total of 15 biopsies from 11 patients were analyzed and the predominant finding was a dense, focal lymphoid infiltrate restricted to the upper dermis with basal cell damage and atrophy of the overlying epidermis. The eruption ran a chronic course from several months to years.

Limitations

Direct immunofluorescence could not be performed except in one case. Immunohistochemical stains for CD4 and CD8 could not be done owing to nonavailability. Phototesting was undertaken in one patient only.

Conclusion

Small grouped papules on the nose and adjoining skin with a lichenoid histopathology appear to represent a distinct clinicopathological entity. It may be related to actinic lichen nitidus/micropapular variant of polymorphous light eruption.

A cross-sectional study of spontaneous repigmentation in vitiligo

Background

Spontaneous regression is well documented in several chronic skin diseases such as psoriasis, alopecia areata, and atopic dermatitis. However, information on vitiligo is scarce.

Aims

We studied the frequency, extent, and factors affecting spontaneous repigmentation in vitiligo.

Methods

A cross-sectional descriptive study was undertaken in 167 patients with vitiligo with an emphasis on history of spontaneous repigmentation. Where available, photographs documenting spontaneous repigmentation were also obtained. Repigmentation was defined as spontaneous if it occurred when the patient was off treatment for at least 3 consecutive months.

Results

Spontaneous repigmentation occurred in 36 (21.5%) patients with complete repigmentation in 6 (3.6%) patients. The extent varied from 0.5% to 100% (mean, 35.4 ± 37.9%) of vitiliginous skin. It occurred after 3 months to 47 years (mean, 8.7 ± 9.5 years) of onset of vitiligo and persisted for 2 months to 27 years (mean, 4.4 ± 6.2 years). Diffuse repigmentation was the most common pattern observed in 20 (55.6%) patients and there was a good color match in 26 (72.2%) patients. Likelihood of spontaneous repigmentation was 3.5 times greater in patients with more than 3 years of stable disease (P = 0.001).

Limitations

The chief limitation was the dependence on patient recall for the data, except when documented by images.

Conclusion

Spontaneous repigmentation occurs in one-fifth of patients with vitiligo. In some patients, the repigmentation is clinically significant and long-lasting. Considering its frequency and extent, spontaneous repigmentation should be taken into account both when evaluating novel interventions and counselling patients about the course of the disease.

Hemi Masticatory Spasm: Series of 7 Cases and Review of Literature

Background

Hemi masticatory spasm (HMS) is a rare movement disorder affecting muscles of mastication attributed to dysfunction of motor branch of trigeminal nerve and is characterized by painful spasm of masticatory muscles. Microvascular compression leading to focal demyelination of motor branch of trigeminal nerve is the most speculated on mechanism of HMS. Treatment options range from medical to surgical approaches, but botulinm toxin (BTX) has now become the preferred treatment.

Cases

We report a retrospective review of 7 cases of HMS, supported by electrophysiological and clinical findings. All the cases had excellent response to BTX therapy.

Discussion and Conclusion

In this article, we highlight the delay in diagnosis of HMS attributed to rarity, long course of illness, association with hemiatrophy, "Lichen Sclerosus et Atrophicus," and scleroderma/morphea. Considering the favorable outcome to BTXs, surgical treatment can be avoided or delayed in majority except secondary cases.

Necrobiotic Xanthogranuloma as the Presenting Manifestation of Smouldering Myeloma

Necrobiotic xanthogranuloma is a rare dermatological manifestation of underlying hematological malignancies, in particular, when associated with paraproteinemia. These patients who are clinically symptomatic with chronic papules, nodules or plaques which demonstrate a histopathological pattern suggestive of extensive and frequently confluent areas of necrobiosis with granulomatous infiltration, warrant evaluation for an underlying monoclonal gammopathy.

Macular hypopigmentation, hair loss and follicular spongiosis: A distinct clinicopathological entity

Background

Hypopigmented macules are seen in a variety of disorders and the diagnosis rests on clinicopathological correlation. However, some cases are difficult to classify and pose a diagnostic challenge.

Aim

To describe the clinical and histopathological features of patients with hypopigmented macules and follicular spongiosis on histopathology.

Materials and Methods

We undertook a retrospective analysis of clinical and histopathological findings in 12 patients who presented with clinically nondiagnostic hypopigmented macules and showed follicular spongiosis on skin biopsy, at All India Institute of Medical Sciences, New Delhi, India between January 2015 and October 2016. The findings were compared with 12 patients with "unclassified" hypopigmented macules, who did not show follicular spongiosis on skin biopsy.

Results

A total of 12 patients with hypopigmented macules showed spongiosis affecting the follicular epithelium on histopathology. There were eight men and four women, most in their second decade (mean age 19.1 ± 8.05 years), presenting with hypopigmented macules most commonly on the upper limbs, for a mean duration of 6.33 ± 5.10 months. Clinically evident lesional hair loss was seen in all patients, and follicular prominences in seven (58%) patients. Histological features suggestive of other diagnosis, namely leprosy, mycosis fungoides or sarcoidosis were not seen in any biopsy. Alcian blue stain revealed an minimal amount of mucin in one biopsy. Clinically apparent hair loss and follicular prominences were found to be statistically significantly associated with histological evidence of follicular spongiosis (P < 0.001 and 0.003, respectively).

Limitations

Our study is limited by its retrospective design and small sample size.

Conclusions

Patients with hypopigmented macules and follicular spongiosis on histopathology may represent a distinct clinicopathological entity that is associated with lesional hair loss and follicular prominences. It is probably a variant of an endogenous dermatitis similar to pityriasis alba.