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A glucagonoma is a rare tumor of the alpha cells of the pancreas that results in up to a 1000-fold overproduction of the hormone glucagon. Alpha cell tumors are commonly associated with glucagonoma syndrome, though similar symptoms are present in cases of pseudoglucagonoma syndrome in the absence of a glucagon-secreting tumor. more...

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Fewer than 250 cases of glucagonoma have been described in the literature since their first description by Becker in 1942. Because of its rarity (fewer than one in 20 million worldwide), long-term survival rates are as yet unknown.


The primary physiological effect of glucagonoma is an overproduction of the peptide hormone glucagon, which enhances blood glucose levels through the activation of catabolic processes including gluconeogenesis and lipolysis. Gluconeogenesis produces glucose from protein and amino acid materials; lipolysis is the breakdown of fat. The net result is hyperglucagonemia, decreased blood levels of amino acids (hypoaminoacidemia), anemia, diarrhea, and weight loss of 5-15 kg.

Necrolytic migratory erythema (NME) is a classical symptom observed in patients with glucagonoma and is present in 80% of cases. Associated NME is characterized by the spread of erythematous blisters and swelling across areas subject to greater friction and pressure, including the lower abdomen, buttocks, perineum, and groin.

Diabetes mellitus also frequently results from the insulin and glucagon imbalance that occurs in glucagonoma. Diabetes mellitus is present in 80-90% of cases of glucagonoma, and is exacerbated by preexisting insulin resistance.


A blood serum glucagon concentration of 1000 pg/mL or greater is indicative of glucagonoma (the normal range is 50-200 pg/mL).

Blood tests may also reveal abnormally low concentrations of amino acids, zinc, and essential fatty acids, which are thought to play a role in the development of NME. Skin biopsies may also be taken to confirm the presence of NME.

A CBC can uncover anemia, which is an abnormally low level of hemoglobin.

The tumor itself may be localized by any number of radiographic modalities, including angiography, CT, MRI, PET, and endoscopic ultrasound. Laparotomy is useful for obtaining histologic samples for analysis and confirmation of the glucagonoma.


Heightened glucagon secretion can be treated with the administration of octreotide, a somatostatin analog, which inhibits the release of glucagon. Doxorubicin and streptozotocin have also been used successfully to selectively damage alpha cells of the pancreatic islets. These do not destroy the tumor, but help to minimize progression of symptoms.

The only curative therapy for glucagonoma is surgical resection, where the tumor is removed. Resection has been known to reverse symptoms in some patients.


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Brittle nails: pathogenesis and treatment
From Journal of Drugs in Dermatology, 1/1/03 by Hendrik Uyttendaele

Brittle nails are a common reason why patients consult a dermatologist. The incidence of brittle nails in the European and North American population is approximately 20%, and women suffer from nail brittleness twice as often as men (1).

There is no concise definition of what constitutes a brittle nail, and there are no characteristic histological findings to help the clinician make this diagnosis. The dermatologist needs to make the diagnosis of brittle nails based on the patient's history and certain non-pathognomonic clinical features. The presenting complaints of patients with brittle nails are often their inability to grow long nails and a description of their nails as soft, dry, weak, or easily breakable. More objective clinical features seen in brittle nails are onychoschizia (transverse splitting), onychorrhexis (longitudinal splitting), and nail plate surface degranulation (2). Brittle nails have been divided into several types including an isolated split at the free edge, lamellar splitting of the free edge, transverse splitting of the lateral edge, and multiple crenellated splitting that resembles the battlements of a castle (3).

Most commonly, a clear-cut etiology for brittle nails cannot be found and hence most cases are labeled as "idiopathic brittleness of the nails." Dehydration due to external influences such as water, detergents, or dehydrating chemicals is often a contributing or causative factor (4). These agents decrease the normal water content of the nail plate, which then results in breakage of the intercellular corneocyte bridges, leading to a fragile and brittle nail plate. Similarly, evaporation of water in the nail plate due to high and low temperatures can result in identical changes (5). Quantitative and qualitative changes in nail keratins may also be induced by chemical and physical insults. Hapalonychia (thinning of the nail plate) due to decrease of the nail matrix length may predispose towards the development of brittle nails. Nails also become more brittle with age. This may be due to the decreased nail growth rates observed in elderly individuals and thus an inherent increased exposure time of the nail plate to environmental factors. Likewise, as skin is drier in the elderly, so too are the nails. A genetic component in the etiology of brittle nails is suggested by the fact that approximately half of patients will report a family member with similar complaints.

Brittle nails may also be found in certain skin diseases such as psoriasis, lichen planus, and alopecia arcata. It is important to recognize these diseases because nail treatment for these disorders are different. Nail brittleness has also been described as an incidental finding in a variety of dermatological disorders such as acanthosis nigricans (6).

It is equally important to rule out systemic etiologies for brittle nails. These include infections such as tuberculosis, endocrinopathies (hypo- and hyperthyroidism (7,8), hypoparathyroidism (9), and pituitary disorders (10)), hypochlorhydria, iron deficiency anemia (11), hemochromatosis (12), arsenical intoxication, glucagonoma (13), osteoporosis, osteomalacia, diseases that cause severe arthritic deformities of the distal joints, Sjogren's syndrome and nutritional disturbances such as cachexia (14), vitamin and zinc deficiencies (15).

The treatment of brittle nails is often difficult. If no precipitating or contributing factors can be elucidated and if the brittle nails have been present for many years, available treatments are often ineffective. However, the initial approach to the treatment of brittle nails should focus on the removal of any exogenous factors that may cause or exacerbate nail fragility. Patients should be instructed not to wash hands frequently and to avoid contact with water or other dehydrating chemicals. Rehydration of the nail plate, cuticle and surrounding nail fold can be obtained by soaking the nails in lukewarm water followed by application of an effective moisturizer. Alpha-hydroxy acid containing moisturizer and preparations that contain hydrophilic substances such as phospholipids have been successfully used for this (16). Occasionally, the once a week use of nail enamel is encouraged to slow water evaporation from the nail plate. It is also recommended that the patients keep their nails short, and clip them after soaking them in lukewarm water.

Numerous therapies have been tried for brittle nails. These include application of essential fatty acids, vitamin c, pyridoxine, iron, vitamin D, calcium, and gelatin (17-19). Several systemic therapies for the treatment of brittle nails have also been tried. Oral iron, primrose oil, pyridoxine and ascorbic acid have been suggested to be of some value (20). More recently biotin, a water-soluble B-complex vitamin, has been demonstrated in several studies to be beneficial in the treatment for brittle nails (21-23). The initial rational for this treatment came from the field of veterinary medicine where biotin had been used for the treatment of pathologic hoof changes in horses (24). An association between deficiency of B-complex vitamins had also been proposed as early as 1940 (25). The recommended daily oral biotin dose is 2.5 mg, with two months being the average time before clinical improvements are observed and the recommended time of treatment is 3-6 months. An increase in nail thickness, decreased lamellar splitting, and decreased irregularities of the dorsal nail plate surface were observed in patients with brittle nails treated with Biotin (21). It is not known how long the improvement in nail strength lasts after cessation of biotin treatment. It also remains unclear how biotin-dependent biochemical mechanisms are responsible for nail plate strength, and whether they are necessary for nail keratin or intercellular cement substance production. Lastly, treatments that would increase the rate of nail growth would be beneficial in the treatment of brittle nails.

In summary, the syndrome of brittle nails may be more than a cosmetic problem. The frayed and fragile nail plate tends to catch on everything and therefore does impact on function, particularly of the fingernails.


(1.) Lubach D, Cohrs W, Wurzinger, R. Incidence of brittle nails. Dermatologica 1986; 172:144-7.

(2.) Tosti A, Piraccini BM. Treatment of common nail disorders. Dermatol Clin 2000; 18:339-48.

(3.) Baran R. Fragilite des ongles. Cutis (France) 1978; 2:457.

(4.) Scher RK, Bodian AB. Brittle nails. Semin Dermatol 1991 10:21-5.

(5.) Scher RK. Brittle nails. Int J Dermatol 1989; 28:515-6.

(6.) Von Fisher F. Acanthosis Nigricans. Dermatologica 1949; 98:319-20.

(7.) Keipert JA, Kelly R. Acquired juvenile hypothyroidism presenting with nail changes. Australas J Dermatol 1978; 19:89-90.

(8.) Mullin GE, Eastern JS. Cutaneous consequences of accelerated thyroid function. Cutis 1986; 37:109-14.

(9.) Yuzuk S, Keren G, Lobel D, Kahana M, Schewach-Millet M. Primary cutaneous manifestation in a child with idiopathic hypoparathyroidism. Int J Dermatol 1986; 25:531-2.

(10.) Wit JM, Beemer FA, Barth PG, Oorthuys JW, Dijkstra PF, Van den Brande JL, Leschot NJ. Cerebral gigantism (Sotos syndrome). Compiled data of 22 cases. Analysis of clinical features, growth and plasma somatomedin. Eur J Pediatr 1985; 144:131-40.

(11.) Djaldetti M, Fishman P, Hart J. The iron content of finger-nails. in iron deficient patients. Clin Sci (Lond) 1987; 72:669-72.

(12.) Chevrant-Breton J, Simon M, Bourel M, Ferrand B. Cutaneous manifestations of idiopathic hermochromatosis. Study of 100 cases. Arch Dermatol 1977; 113:161-5.

(13.) Chao SC, Lee JY. Brittle nails and dyspareunia as first clues to recurrences of malignant glucagonoma. Br J Dermatol 2002; 146:1071-4.

(14.) Runne U, Orfanos CE. The human nail: structure, growth and pathological changes. Curt Probl Dermatol 1981; 9:102-49.

(15.) Brazin SA, Johnson WT, Abramson LJ. The acrodermatitis enteropathica-like syndrome. Arch Dermatol 1979; 115:597-9.

(16.) Finlay AY, Frost P, Keith AD, Snipes W. An assessment of factors influencing flexibility of human fingernails. Br J Dermatol 1980; 103:357-65.

(17.) Brehm G. Therapie der onychorrhexis. Dtsch Med Wochenschr 1987; 112:980.

(18.) Lubach D, Wurzinger, R. Trace elements in samples of brittle and nonbrittle finger nails. Derm Beruf Umwelt 1986; 34:37-9.

(19.) Zaun H. Bruchige Fingernagel. Dtsch Med Wochenschr 1987; 112:198-9.

(20.) Campbell AJ, McEwan GC. Treatment of brittle nails and dry eyes. Br J Dermatol 1981; 105:113.

(21.) Colombo VE, Gerber F, Bronhofer M, Floersheim GL. Treatment of brittle fingernails and onychoschizia with biotin: scanning electron microscopy. J Am Acad Dermatol 1990; 23:1127-32.

(22.) Floersheim GL. [Treatment of brittle fingernails with biotin]. Z Hautkr 1989; 64:41-8.

(23.) Hochman LG, Scher RK, Meyerson MS. Brittle nails: response to daily biotin supplementation. Cutis 1993; 51:303-5.

(24.) Comben N, Clark RJ, Sutherland DJ. Clinical observations on the response of equine hoof defects to dietary supplementation with biotin. Vet Rec 1984; 115:642-5.

(25.) Silver H. Nail and nail changes. J Invest Dermatology 1940; 3:357-73.

Richard K. Scher MD

Department of Dermatology

Columbia University

161 Fort Washington Avenue

New York, NY 10032

Phone: (212) 305-8444



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