MedUrgent

  INTESTINAL HELMINTHS   Introduction Soil transmitted Helminthiasis includes Ascaris lumbricoides, Trichuris trichiura, Ancylostoma dudenale and Necator americanus. About one third of the global population is infected and it is an important cause of physical and intellectual retardation. It is most commonly seen in worm and moist climates and in areas where there is poor sanitation, poor hygiene and unsafe water supply. It is more prevalent in developing countries in Africa, South East Asia, China and South America. Morbidity depends on the heaviness of the infection.   ASCARIASIS  Life cycle Ascaris lumbricoides infection is acquired by swallowing of embryonated ova from soil contaminated by human faeces. After being swallowed, the ova penetrate the intestinal wall, passes to the liver and thence through the systemic circulation to the lungs. There, it penetrates the alveoli, passes up the respiratory system to be swallowed again and develop into adults that ...

   SNAKE BITES & SCORPION STINGS Snakes and scorpions secrete venom by means of special glands when they bite  or sting humans. The venom is secreted into the torn skin when the snake takes a bite or else it may be injected through a wound that is caused by the scorpion's thorn. The scorpion's venom is placed in a reservoir in its tail from where it is injected. Snakes preserve their venom in the parotid gland and are passed to humans through the frontal fangs. The clinical effect of the poison depends on the amount of venom injected, age of the patient, site of the bite and effectiveness of the treatment, however, with a scorpion sting, the effect is not in proportion to the amount of venom injected. SNAKE BITES Though most of snake venoms are lethal, mortality and morbidity are low. There are 3 families of snakes which are poisonous. All have fangs at the front of their mouths by which the venom is injected from the parotid glands. These are: a) Elapidae whi...

 Mycetoma (Madura Foot) This is a chronic granulomatous disease that affects mainly the limb but it can be seen on the abdominal wall and chest. The disease is caused by Actinomycetes (transitional forms between bacterai and fungi) and Eumycetes (true fungi). It is endemic in Africa, India, South and Central America. Clinical: Madura Foot is common among field workers who contract it from soil. The causative organism spreads from the skin into deeper tissue forming granuloma and discharging sinuses. The color of the discharge from these sinuses varies with the causative organism(e.g. black color discharge is caused by Madurella mycetomatis, white and yellow dicharge by Actinomadura madurae, red colored discarge by Actinomadura pelletieri) Bacterial causes include Nocardia (yellow discarge) and Streptomyces (yellow or red discharge). The disease leads to swelling, deformation and loss of function of the affected limb. Investigations -Fine needle aspirate -Tissue biopsy -...

  Podoconiosis This is a non-filarial type of elephantiasis. It is caused by exposure to irritant soil and soil metals e.g. selenium and aluminum that can penetrate through bare feet skin into the lymphatic vessels and nodes leading to obstruction the lymphatic system, swelling and disfigurement of the feet including fusion of toes. The disease is common in Africa and it affects children above 5 years and adults. Clinical The affected limb (usually bilateral) is swollen with lymphedema, shows multiple nodules, hyperkeratosis, ulceration and super-infection (Mossy Foot). Treatment -The use of shoes is protective especially in high altitude areas with volcanic soil -Vigorous foot hygiene -Compression wrapping -Physiotherapy -Surgery

  LOIASIS  This is a filarial disease caused by the filarialworm loa loa which is transmitted by the horse fly, Chrysops. Migration of the larva in the subcutaneous area and deep tissue leads to itching, pain and parasthesia. Immune response to the adult worm leads to formation of Calabar swellings under the skin of the face, eye lids and forearms. These swellings last for several hours to several days and recur at different intervals. The worm can be seen migrating beneath the conjunctiva where it causes severe itching.  LABORATORY TESTS • Blood film during the day (unlike W.bancrofti). • Serology • High eosinophil count TREATMENT 1. Diethylcarbamazine: start at a small dose of 1mg/kg/day and build up gradually 2. Steroids to reduce the inflammation 3. In mixed infections with O.volvulus, use Ivermectin instead of DEC for fear of the Mazzotti reaction (tenderness and severe itching of the swelling and the regional lymph nodes associated with malaise and low...

  TROPICAL PULMONARY EOSINOPHILIA It is common in areas where Bancrofti filariasis is endemic. It is due to entrapment of microfilaria of W.Bancrofti and W.Brugiya within the lungs where they elicit an eosinophilia hypersensitivity reaction. Clinical features Nocturnal cough and wheezes, malaise and loss of weight are common presenting symptoms. Eosinophil count is very high and chest X-ray may be normal or more commonly shows reticular appearance similar to miliary mottling. Pulmonary fibrosis occurs later. Treatment Diethylcarbamazine 5mg/kg/day in 3 divided doses for 3 weeks. A second course may be required. Anti-filarial drug activity:

  HIV INFECTIONS AND AIDS Human immunodeficiency viruses HIV 1 and HIV 2 cause AIDS. In the year 2006, more than 25 million African adults and children were estimated to be living with HIV. The routes of transmission of the infection include unprotected sexual intercourse, mother to child transmission, transfusion of infected blood products, unsterile needles and surgical instruments. The virus attacks mainly the CD4-T lymphocytes where it replicates and gradually destroys these cells and as their number decreases immunosuppression state prevails (when CD4 is<200 cells/mm3). This predisposes the patient to some opportunistic infections and virus related tumors e.g. lymphoma and Kaposi sarcoma. CLINICAL PRESENTATION 1- Acute retroviral illness: Occurs 2-5 weeks after infection and lasts for 3-21 days. It is characterized by malaise, fever, anorexia, sore throat, myalgia, arthralgia, headache, diarrhea, maculopapular rash and generalized lymphadenopathy, a picture similar to...