[Assessment of diabetic alterations of microcirculation by means of capillaroscopy and laser-Doppler anemometry]

BACKGROUND

Only minor changes of skin capillary morphology have been described in diabetic patients by means of capillaroscopy, whereas cutaneous microvascular dysfunction is well known. We examined correlations between functional and morphological abnormalities of the capillaries in Type 1 and 2 diabetic patients and the influence of diabetes duration on capillary morphology.

PATIENTS AND METHODS

Density, diameters and morphology of nailfold capillaries were investigated in diabetic patients, 16 Type 1 and 19 Type 2, and compared to age- and sex-matched control groups. Capillary blood cell velocities (CBV) during rest and after 3-minute arterial occlusion were measured in the dorsal middle phalangeal area of the left ring finger by means of laser Doppler anemometry.

RESULTS

Capillary density, width and arterial limb diameter were similar in Type 1 and 2 diabetic patients compared to their controls. Capillary diameters of the apical part and the venous limb were enlarged in the combined analysis of Type 1 and 2 diabetic patients compared to the control group (apex: 19.2 +/- 0.6 microns vs 17.4 +/- 0.6 microns, p = 0.0243; venous limb: 17.3 +/- 0.5 microns vs 15.9 +/- 0.4 microns, p = 0.0238). Tortuous capillaries were more often observed in Type 1 (n = 13 vs n = 7, p = 0.028) and 2 diabetic patients (n = 16 vs n = 9, p = 0.019) than in controls. In Type 1 diabetic patients an inverse correlation (r = -0.52; p = 0.019) was found between capillary density and resting CBV. In Type 2 diabetic patients capillary apex diameter correlated positively with peak CBV (r = 0.49; p = 0.017). Disease duration correlated inversely with arterial limb diameter (r = -0.48; p = 0.020) and width of the capillaries (r = -0.48; p = 0.018) in Type 2 diabetic patients.

CONCLUSION

Tortuous and dilated capillaries, indicating microangiopathy, were found in the skin of diabetic patients by means of capillaroscopy. Using laser Doppler anemometry it is possible to assess impairment of postocclusive reactive hyperemia, due to diabetic microvascular dysfunction, in single capillaries. Correlations between morphological and functional microcirculatory alterations in diabetes may be explained by hemodynamic changes, depending on diabetes duration.

Onychomatricoma: report of a case and its comparison with fibrokeratoma of the nailbed

Onychomatricoma was first described in 1992 by Baran and Kint. Twenty cases have been reported to date, all of which are from Europe. This tumor has characteristic clinical, light microscopic, and ultrastructural features which have recently been refined andjustify its categorization as a novel tumor of the nail matrix. We examined a specimen sent in consultation by a large reference laboratory; despite improper orientation and absence of the involved nail plate, it had microscopic characteristics consistent with onychomatricoma. Soon thereafter, a second patient presented with a tumor arising in the nailbed that bore a superficial resemblance to onychomatricoma but showed the microscopic features of fibrokeratoma. We discuss the differentiation between these two lesions and point out that a distinction can be made even when incomplete material is submitted for review. To our knowledge, this is the first example of onychomatricoma to be reported from North America.

Two kinds of Hutchinson's sign, benign and malignant

We examined 6 subungual melanomas in situ and 18 melanocytic nevi and compared pigmentation of the nail plates and hyponychium with the use of a dermatoscope. Hutchinson's sign on the hyponychium was not always evidence of subungual melanoma because it can be seen in both diseases. However, there was a wide difference in their dermatoscopic features. We believe that observation of pigmentation on the hyponychium with the use of a dermatoscope contributes to the precise diagnosis of subungual melanoma.

Yellow nail syndrome: does protein leakage play a role?

Yellow nail syndrome is characterized by primary lymphoedema, recurrent pleural effusion and yellow discoloration of the nails. Although mechanical lymphatic obstruction is assumed to be the underlying pathology, it cannot explain the common finding of high albumin concentration in the pleural space. This paper describes a case of yellow nail syndrome presenting with the classical triad of lymphoedema, recurrent pleural effusion and yellow discoloration of the nails, associated with persistent hypoalbuminaemia and increased enteric loss of albumin. Based on the findings in this case and those in the literature, it is speculated that increased microvascular permeability may contribute to the pathogenesis of this syndrome.

Thallium poisoning in Israel

We report the first case of thallium poisoning in Israel in almost 30 years. A 40-year-old man was apparently poisoned by a business associate when, on several occasions, he unknowingly drank an alcoholic beverage containing the toxic substance. Delayed admission and recurrent thallium ingestion resulted in both acute and chronic symptoms being present concomitantly. Conventional treatment modalities (Prussian blue and forced diuresis) were employed. The patient survived, although neurological sequelae ensued. The problems encountered in diagnosis and treatment of this relatively uncommon entity are discussed.

Squamous cell lung cancer with solitary subungual metastasis

Subungual metastasis resulting from internal malignancies is an extremely rare event. A few cases of subungual metastasis from lung cancer have been reported. However, subungual metastasis arising from lung cancer without any other form of distant metastases has not been reported. The misdiagnosis of a solitary subungual metastases as a benign inflammatory lesion is an important problem as it may cause the misdiagnosis of a lower stage of lung cancer. We may be reporting the first case of a subungual metastasis from lung cancer without any other distant metastases.

Onychomatricoma with misleading features

Onychomatricoma is a rare tumour of the nail matrix with peculiar clinical and histological features and electron microscopic findings. We report on 5 cases with appearances which were misleading. Three presented as longitudinal melanonychia, a previously unreported observation. One case had the appearance of a cutaneous horn. In 3 of the 5 cases the tumour was associated with an onychomycosis and this may thus have been a predisposing factor in the secondary fungal infestation. Onychomatricoma appears as a multi-faceted tumour which can be mimicked by longitudinal melanonychia and/or onychomycosis.

Relapses of onychomycosis after successful treatment with systemic antifungals: a three-year follow-up

BACKGROUND

Data about relapses of onychomycosis after treatment with the new systemic antifungals vary among the different studies, with figures ranging from 3 to 20% for terbinafine and from 21 to 27% for itraconazole, depending on the follow-up duration.

OBJECTIVE

To determine the prevalence of relapses of onychomycosis cured by terbinafine compared with that of onychomycosis cured by itraconazole.

METHODS

We followed up 47 patients whose toenail onychomycosis had been mycologically cured in an open randomized study comparing intermittent itraconazole treatment with continuous terbinafine treatment and intermittent terbinafine therapy. Patients were examined every 3 months for up to 3 years after the end of therapy. At each visit clinical and mycologic (direct microscopy and cultures) evaluations were performed.

RESULTS

Eight of the 36 patients (22.2%) who completed the study had a relapse of onychomycosis during the follow-up period, including 2 patients of the terbinafine 250 mg group, 2 patients of the terbinafine 500 mg group and 4 patients in the itraconazole 400 mg group. As the original infection, the relapse was caused in all cases by Trichophyton rubrum.

CONCLUSIONS

This study shows that 22.2% of patients with onychomycosis successfully treated with systemic antifungals experienced a relapse. The relapse rate increased from 8. 3% at month 12 to 19.4% at month 24 and to 22.2% at month 36. Relapses were more common in patients treated with pulse itraconazole (4/11) than in patients treated with continuous (2/12) or intermittent (2/13) terbinafine. Statistical analysis did not reveal any significant difference between relapse rates in the three groups.

Onychomycosis due to Trichophyton soudanense in Switzerland

We report 2 cases of onychomycosis of the finger- and toenails due to Trichophyton soudanense with a typical clinical picture different from the hyperkeratosis of T. rubrum subungual onychomycosis.

Sporadic congenital leukonychia with partial phenotype expression

GOAL

To describe the characteristics and inheritance pattern of a case of congenital leukonychia.

OBJECTIVES

1. To describe the etiologies of congenital and acquired leukonychia. 2. To discuss the differential diagnosis of leukonychia. 3. To outline inheritance patterns associated with leukonychia.

Reconstruction of a double nail deformity: a case report

We report the successful reconstruction of a double nail deformity after fingertip injury. Double nail growth is rather rare. In our case it was not of congenital origin. Double nail deformity results from implantation of the nail matrix associated with damage to the finger tip. We excised the second nail and reconstructed the remaining nail bed using a part of the excised one. The vertical growth of the first nail was also corrected. Four months later, successful regeneration of the nail was observed.

Drug-induced and traumatic nail problems in the haemophilias

Many persons with haemophilia suffer from HIV and receive highly active antiretroviral therapy. Three patients received indinavir and required surgery due to ingrown toenails. Two patients suffered from a traumatic subungual haematoma. The treatment protocol is described whereby the pressure exerted onto the germinal layer and the nail bed is relieved in order to alleviate pain and nail matrix damage.

Nail changes in Langerhans cell histiocytosis

Nail changes in Langerhans cell histiocytosis are distinctly uncommon. Paronychial erythema, swelling and subungual pustules of the fingernails and toenails were cardinal, and were supported by diffuse as well as dense collections of mononuclear Langerhans cells evidenced by microscopic investigation. Oral administration of co-trimoxazole (800 mg sulphamethoxazole + 160 mg trimethoprim) every 12 h, 50 mg/d cyclophosphamide and 80 mg/d predinisolone were the mainstay of treatment, supported by scalp tar shampoo and local betamethasone lotion application.

Dystrophic psoriatic fingernails treated with 1% 5-fluorouracil in a nail penetration-enhancing vehicle: a double-blind study

BACKGROUND

Topically applied nail therapeutics need to permeate the nail plate to reach the nail bed or nail matrix and exert their potential beneficial effect at these locations to obtain a therapeutic benefit. So far only topically applied 5-fluorouracil on affected nails of psoriatic patients has been shown to produce a notable clearance. Vehicle formulations enhancing nail permeation processes are thought to increase the concentration of the active agent and therefore therapeutic efficacy, possibly enabling the use of a low concentration of the active agent thereby lowering the incidence of adverse effects.

OBJECTIVE

This study was designed to verify whether a recently developed nail penetration enhancer in a lotion formulation, Belanyx((R)) (urea, propylene glycol), improves the efficacy of a low concentration of 5-fluorouracil (1%) in psoriatic fingernail lesions.

METHODS

In a randomised, double-blind, left-right study the efficacy of 1% 5-fluorouracil in the Belanyx vehicle was compared to the vehicle preparation Belanyx in dystrophic fingernails of 57 psoriatic patients. Both preparations were applied in a once daily regimen for 12 weeks. Responses and adverse effects of one selected target nail were recorded at screening, at baseline and at weeks 2, 4, 8 and 12 of treatment with a final assessment at week 16: 4 weeks after the end of treatment. As parameter of efficacy was chosen the total nail area severity (NAS) score, consisting of the separate parameters nail pitting area, number of nail pits, subungual keratosis, onycholysis, oil spots and the various scores of overall improvement.

RESULTS

The efficacy of 1% 5-fluorouracil in lotion and that of the vehicle in suppressing the parameters of dystrophy were shown to be similar at the end of treatment (p = 0.063) or follow-up (p = 0.130). Both preparations produced statistically significant improvements (p </= 0.05) for almost all assessed parameters after 12 weeks of treatment and after the 4 weeks of follow-up. For Belanyx lotion this applied to the nail pitting area, the number of nail pits, subungual keratosis, onycholysis and oil spots. The investigators' and patients' opinion of overall improvement of severity as well as the total NAS score of one target nail likewise showed a statistically significant improvement at the end of treatment and at the end of the observation period (p </= 0.05). With the 1% 5-fluorouracil lotion the same statistically significant improvements were obtained in all of the assessed symptoms with the exception of the number of pits and onycholysis at week 12 and week 16. Possible treatment-related adverse effects were established in 6 patients showing inflammation and infection (3 patients) or discoloration (5 patients); 3 patients on 5-fluorouracil lotion showed onycholysis.

CONCLUSION

Addition of 1% 5-fluorouracil to the nail permeation enhancer Belanyx does not increase the efficacy of the active agent in psoriatic nail dystrophy of this study population. The obtained results also suggest that Belanyx lotion can be used in this indication since it has shown a favourable efficacy-safety ratio.

An evaluation of the relevance of routine DNA typing of fingernail clippings for forensic casework

DNA extracted from fingernail clippings of victims in forensic cases is a possible source of DNA from the perpetrator in cases where victims struggled or defended themselves. The source of this DNA on a victim's fingernails could possibly originate from contact with the suspect's blood, saliva, semen or scratched skin. In this technical note we evaluate the relevance of routine DNA typing of fingernail clippings in the forensic biology laboratory when, in real casework, normally only small quantities of nail material is sent. This was carried out by extracting DNA from fingernail clippings from a number of volunteers, before and after aggressively scratching other volunteers. No blood was drawn from the scratching, but skin flakes were observed under the nails before cutting and subsequent DNA typing. The DNA extracted was then typed using the STR systems: HUMTHO1, HUMTPOX and HUMCSF1PO (CTT triplex) and the system of D1S80. These profiles were compared with profiles achieved by similar typing of buccal swabs as a reference from each volunteer. In this study, the profile detected from each volunteer's clippings was the same before and after scratching, and matched the profile of the corresponding volunteer as defined by typing each volunteer's reference buccal swab. Fingernail clippings that are sent to our lab in actual casework are usually so small that additional treatment by swabbing or removing debris from below the clipping is not possible. For this reason, in this simulation the entire clippings were used for DNA extraction, to maximize the possibility of finding an additional profile. In conclusion, the findings from this study show that although the profiles obtained when typing fingernail clippings are those of the donors themselves, we suggest that typing of fingernail clippings should be carried out in forensic cases only when relevant. We would suggest that fingernail clippings not be routinely sent to the biology laboratory as items of evidence to be tested.

Nailfold videocapillaroscopy assessment of microvascular damage in systemic sclerosis

OBJECTIVE

To correlate microvascular abnormalities, evaluated by nailfold videocapillaroscopy (NVC), with the duration of both Raynaud's phenomenon (RP) and systemic sclerosis (SSc) from the date of diagnosis, in a large number of patients with SSc.

METHODS

Ninety-seven consecutive patients were recruited and distributed into 3 groups on the basis of the morphological NVC patterns observed: "early" (E), "active" (A), and "late" (L). In each group the age of patients, age at onset, and the duration of RP as well as of overt SSc were investigated and correlated with the different NVC pattern variables.

RESULTS

The early appearance of giant capillaries and hemorrhages (E pattern) is of great relevance for the early diagnosis of SSc. Therefore, these alterations are more evident in the active phase of the disease (A pattern). Conversely, the NVC observation of loss of capillaries and vascular architectural disorganization and the presence of ramified/bushy capillaries (L pattern) represents the clearest aspect of advanced SSc microvascular damage. These morphological alterations were found to correlate significantly with the duration of both RP and SSc, as well as with age of patients (p = 0.0001). No significant differences were observed when the variables were analyzed in the patients classified as having limited cutaneous SSc or diffuse cutaneous SSc.

CONCLUSION

Classification of defined major nailfold patterns may be useful in assessing the appearance and progression of sclerodermic microangiopathy. As well, nailfold changes might represent a morphological reproduction of the evolution of SSc.

Hydroxyurea-induced nail pigmentation in HIV patients

Hydroxyurea (HU), a cytotoxic agent used in myeloproliferative disorders, has recently been introduced as an adjunct to combination anti-retroviral therapy. We describe abnormal nail pigmentation in four HIV-seropositive patients treated with HU and discuss the likely factors associated with its development.

Clinical pallor is useful to detect severe anemia in populations where anemia is prevalent and severe

Clinical pallor is recommended as a simple way to detect severe anemia, but more data are needed on its accuracy and usefulness when assessed by nonphysicians in diverse settings. We measured hemoglobin and trained non-physician health workers to assess clinical pallor of the conjunctiva, palm and nail beds in five population samples in Nepal and Zanzibar, where severe anemia is common. In total, 5,760 individuals were examined, 3,072 of whom were anemic and 192 of whom had severe anemia (hemoglobin <70 g/L). The prevalence of pallor did not correspond to the prevalence of anemia or severe anemia in the groups studied. However, in all studies, pallor at each anatomical site was associated with a significantly lower hemoglobin concentration. The relative performance of different anatomical sites was not consistent among studies, and we recommend that multiple sites be assessed. Pallor at any of the three sites detected severe anemia with >84% specificity. However, the sensitivity varied from 81% in Nepalese postpartum women to 29% in Zanzibari preschoolers in 1996. Overall estimates for sensitivity and specificity were 50 and 92%, respectively. Although imperfect, use of pallor to screen and treat severe anemia by primary care providers is feasible and worthwhile where severe anemia is common. Usually, the majority of persons with severe anemia will be detected at practically no cost. Many people who are not severely anemic will also receive treatment, but the costs of this error are low compared to the benefits.

Drug-induced nail disorders: incidence, management and prognosis

A large number of drugs of different classes, ranging from antibacterials to chemotherapeutic agents to psoralens, can be responsible for the development of nail changes. Drug-induced nail changes usually involve several or all 20 nails and appear in temporal correlation with drug intake. Some nail changes are asymptomatic and only cause cosmetic problems, while others cause pain and discomfort and impair manual activities or deambulation. Drug-induced nail abnormalities are usually transitory and disappear with drug withdrawal, but sometimes persist in time. The pathogenesis of the nail changes is usually a toxic effect of the drug on the different nail constituents, but other mechanisms can be involved. Drugs that are well known to produce nail abnormalities include cancer chemotherapeutic agents, psoralens, retinoids, tetracyclines, antimalarials and zidovudine. Arsenic poisoning is also always associated with nail changes that have medico-legal importance. Some drugs taken during pregnancy may impair nail development of the fetus, and nail hypoplasia or other nail dystrophies will be evident in the newborn.