Tropical Endocrinology – Part I

Tropical Endocrinology – Part I

Tropical endocrinology is a challenging field of endocrinology. The tropics influence endocrine health in various ways. The overall status of nutritional health, shortcomings in the health care system, and an inadequate number of qualified endocrinologists and endocrine nurses impacts endocrine health as well as care.

There are specific endocrine syndromes, however, which are more common in some parts of the tropics. Some diseases trace their etiology to malnutrition, such as rickets and osteomalacia, to substandard health care, e.g., Sheehan’s syndrome, or to delayed endocrine care, e.g., cretinism and end-stage renal disease or blindness due to diabetic retinopathy. Endocrinopathy can be due to infections, such as tubercular Addison’s disease and HIV-associated lipodystrophy, or can predispose to infections, as seen in Cushing’s syndrome and uncontrolled diabetes.

In this multinational interview, with experienced endocrinologists from three continents, our Education Editor, Sanjay Kalra, explores the wide spectrum of Tropical endocrinology.

1. What endocrine diseases do you encounter in Africa, which are not frequently seen in other parts of world?

Dr Ahomagnon SD Tonami, Benin Republic

Benin city

A Beautiful landscape view of Ikpoba Hill in Benin city

African endocrinology is full of clinical challenges which make our practice stimulating and meaningful. For the African physician, endocrinology is an acute as well as chronic superspecialty. We encounter diabetic ketoacidosis triggered by malaria, limb-threatening diabetic foot with co-existing neuropathic, ischemic and infectious pathology, Basedow’s disease in male patients, and thyroid storm frequently. Sepsis is a common complication of uncontrolled Cushing’s syndrome and diabetes mellitus. Iatrogenic Cushing’s syndrome, as well as Addison’s disease secondary to withdrawal of dermatocorticoid preparations, are frequent. Dark-skinned persons exhibit unique signs such as ‘insulin tattoos’ due to repeated insulin injections at the same site, and depigmentation of skin in secondary adrenal insufficiency. The syndemics of diabetes with tuberculosis and HIV/AIDS are also more common in Africa. Societal attitudes towards obesity, and limited literacy regarding complications of untreated endocrinopathy are an obstacle to proper endocrine care.

Yet, we feel blessed, that as endocrinologists, we are able to contribute to the health and well-being of our countrymen and women.

2. What endocrine diseases do you see in the Caribbean which are not common elsewhere?

Dr Fritz-Line Velayoudom, Guadeloupe, French West Indies

People at the outdoor market in Guadeloupe

The Pointe-a-Pitre Market in Guadeloupe

Endocrine disease seen in Caribbean is similar to that encountered across the world.

However, some diseases which are more frequent include type 2 diabetes that presents with severe ketoacidosis, but allows rapid insulin withdrawal in less than 2 months; idiopathic gynecomastia in young males; hematocele and macronodular goiter in young adults, sometimes familial; and idiopathic hyperaldosteronism.

We often have hypoglycemia secondary to situations of hyperinsulinism in children and young adults, some of whom may be overweight. Environmental factors such as sand pollution, or use of preservatives in food (to withstand high temperatures or transport by sea, as many products are imported) may explain this phenomenon to a certain extent.

3. Fasting and pilgrimages are an integral part of life in many people. Which endocrine complications do such persons experience?

Dr Shehla Shaikh, India

Fasting, though conventionally associated with Islam, is also observed by other religious groups, e.g., Jain community during their pilgrimage to Palitana. Buddhists, Christians and Hindus also observe various intermittent or long-term fasts of varied intensity.

Fasting is conventionally associated with alterations in sleep pattern, circadian rhythm and cortisol rhythm. The rigors of fasting are exacerbated in a pilgrimage due to increased physical activity and inattention to health due to preoccupation with the completion of spiritual commitments. Fasting may be associated with hyperglycemia and diabetic ketoacidosis,hypoglycemia,dehydration and thrombosis in diabetic patients.

There is an increased incidence of infections esp. respiratory and foot injuries during busy pilgrimages such as the Hajj. Thyroid dysfunction is more common due to inability to take medicine as prescribed. Patient education is the key to prevent these complications.

4. How is osteocrinology (bone and mineral disease) unique in developing countries?

Dr Ketut Suastika, Indonesia

Ubud, Indonesia

Local street market, Ubud, Indonesia

Osteocrinology is a major contributor to endocrine practice in the tropics. In our experience, levels of Vitamin D in Indonesia are lower than the usual normal range. Calcium deficiency is rare. Primary hyperparathyroidism though rare, is symptomatic. As chronic kidney disease is managed better, renal osteodystrophy is not encountered frequently nowadays. Glucocorticoid induced osteoporosis is rampant, since exogenous Cushing’ssyndrome and diabetes secondary to steroid use (from traditional or herbal medicine) is so frequent in our country. Charcot’s foot is not uncommon in poorly controlled diabetes.

5. Is tropical diabetes a “real” syndrome? What does this imply to you?

Dr S.V. Madhu, India

Tropical Diabetes is diabetes associated with chronic malnutrition and seen in the tropics. Whether this is a distinct entity is debatable. Earlier classifications of diabetes mellitus included Malnutrition related diabetes mellitus (MRDM) and later Malnutrition modulated diabetes mellitus (MMDM) as a distinct entity based on extensive data generated from India and other Tropical countries. It is no longer classified as a separate entity.

However, endocrinologists practicing in the tropics do face unique challenges. These include a high incidence of acute complications such as ketoacidosis, foot ulcers, tuberculosis and other infections. Jamaican vomiting sickness and Indian lychee induced encephalopathy, both due to hypoglycemia, are some examples of “tropical dysglycemia”.