Typhoid Fever in the African

A CAJM article on typhoid in 1950's Africa.In early days in tropical Africa, typhoid fever was said by the pioneer doctors to be rare. With the growth of cities, often in advance of waterborne sanitation, typhoid fever is now one of the commonest fevers encountered. Whereas paratyphoid A and B are rarely encountered, Salmonella typhi is the usual organism responsible for enteric fever in Africa. Although there are no essential differences in typhoid fever in the African, the disease appears unusual to doctors trained in countries where it is rare, though their fathers of some 50 years ago would be quite at home now in the typhoid wards of an African hospital during an epidemic

Practice of Tropical Medicines

A CAJM article on the practice of tropical medicine.The practice of tropical medicine in London tends to pose rather a different proposition from what it is popularly supposed to be. It does not take long for the consultant to recognise that the tropical side is just but one facet of the composite picture. He soon finds himself in a morass of differential diagnosis when faced with the gamut of those diseases which man is heir to. For, wedged in between what is thought to be malaria, amoebic dysentery, sprue and helminthic infections—or what have you—there are possibilities of a more mundane nature which have to be considered

The Fevers of Africa: Leishmaniasis South of the Sahara

A CAJM article on the disease Leishmaniasis in Sub Saharan Africa of the 1950's.Leishmaniasis was first described from India as the visceral form kala azar; since then this disease has been found to occur in China, Central Asia, Arabia, North Africa, the Sudan. Kenya and sporadically across Africa south of the Sahara to the West Coast. Different varieties of the disease have been described on clinical, epidemiological and parasitological grounds, but these differences are possibly caused by varying degrees of immunity in the human host and the differing habits of the sandfly vector

Pentamidine Dosage: A Base/Salt Confusion

Pentamidine has a long history in the treatment of human African trypanosomiasis (HAT) and leishmaniasis. Early guidelines on the dosage of pentamidine were based on the base-moiety of the two different formulations available. Confusion on the dosage of pentamidine arose from a different labelling of the two available products, either based on the salt or base moiety available in the preparation. We provide an overview of the various guidelines concerning HAT and leishmaniasis over the past decades and show the confusion in the calculation of the dosage of pentamidine in these guidelines and the subsequent published reports on clinical trials and reviews. At present, only pentamidine isethionate is available, but the advised dosage for HAT and leishmaniasis is (historically) based on the amount of pentamidine base. In the treatment of leishmaniasis this is probably resulting in a subtherapeutic treatment. There is thus a need for a new, more transparent and concise guideline concerning the dosage of pentamidine, at least in the treatment of HAT and leishmaniasi

Atomic data for neutron-capture elements I. Photoionization and recombination properties of low-charge selenium ions

We present multi-configuration Breit-Pauli AUTOSTRUCTURE calculations of distorted-wave photoionization (PI) cross sections, and total and partial final-state resolved radiative recombination (RR) and dielectronic recombination (DR) rate coefficients for the first six ions of the trans-iron element Se. These calculations were motivated by the recent detection of Se emission lines in a large number of planetary nebulae. Se is a potentially useful tracer of neutron-capture nucleosynthesis, but accurate determinations of its abundance in photoionized nebulae have been hindered by the lack of atomic data governing its ionization balance. Our calculations were carried out in intermediate coupling with semi-relativistic radial wavefunctions. PI and recombination data were determined for levels within the ground configuration of each ion, and experimental PI cross-section measurements were used to benchmark our results. For DR, we allowed dn=0 core excitations, which are important at photoionized plasma temperatures. DR is the dominant recombination process for each of these Se ions at temperatures representative of photoionized nebulae (~10^4 K). To estimate the uncertainties of these data, we compared results from three different configuration-interaction expansions for each ion, and tested the sensitivity of the results to the radial scaling factors in the structure calculations. We find that the internal uncertainties are typically 30-50% for the direct PI cross sections and ~10% for the computed RR rate coefficients, while those for low-temperature DR can be considerably larger (from 15-30% up to two orders of magnitude) due to the unknown energies of near-threshold autoionization resonances. The results are suitable for incorporation into photoionization codes used to numerically simulate astrophysical nebulae, and will enable robust determinations of nebular Se abundances.Comment: 17 pages, 8 figures, accepted for publication in Astronomy and Astrophysic

Reiter's syndrome following shigella flexneri 2a

Shigella flexneri 2a was isolated from a patient with Reiter's syndrome (RS) following a family outbreak of traveler's diarrhea. Among 3 members at risk, only the patient was positive for HLA-B27. Data from 3 similar families support the hypothesis that susceptibility to RS is genetically transmitted. It is urged that every effort be made to culture and subtype Shigella and other enteric pathogens in RS following diarrhea. Concurrently, the patient had hepatitis, interpreted as a parallel enteric infection.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37731/1/1780200117_ftp.pd

An assessment of the usefulness of a rapid immuno-chromatographic test, "Determine™ malaria pf" in evaluation of intervention measures in forest villages of central India

BACKGROUND: Plasmodium falciparum malaria, is a major health problem in forested tribal belt of central India. Rapid and accurate methods are needed for the diagnosis of P. falciparum. We performed a blinded evaluation of the recently introduced Determine™ malaria pf test (Abbott, Laboratories, Japan) compared with microscopy and splenomegaly in children in epidemic prone areas of district Mandla to assess the impact of intervention measures. METHODS: Children aged 2–10 yrs with and without fever were examined for spleen enlargement by medical specialist by establishing a mobile field clinic. From these children thick blood smears were prepared from finger prick and read by a technician. Simultaneously, rapid tests were performed by a field lab attendant. The figures for specificity, sensitivity and predictive values were calculated using microscopy as gold standard. RESULTS: In all 349 children were examined. The sensitivity and specificity for Determine rapid diagnostic test were 91 and 80% respectively. The positive predictive values (PPV), negative predictive values (NPV) and accuracy of the test were respectively 79, 91 and 85%. On the contrary, the sensitivity and specificity of spleen in detecting malaria infection were 57 and 74 % respectively with PPV of 73%, NPV 59 % and an accuracy of 65%. CONCLUSIONS: Determine™ malaria rapid diagnostic test is easier and quicker to perform and has other advantages over microscopy in not requiring prior training of personnel or quality control. Thus, highlighting the usefulness of a rapid antigen test in assessing prevailing malaria situation in remote areas

Understanding Human-Plasmodium falciparum Immune Interactions Uncovers the Immunological Role of Worms

BACKGROUND: Former studies have pointed to a monocyte-dependent effect of antibodies in protection against malaria and thereby to cytophilic antibodies IgG1 and IgG3, which trigger monocyte receptors. Field investigations have further documented that a switch from non-cytophilic to cytophilic classes of antimalarial antibodies was associated with protection. The hypothesis that the non-cytophilic isotype imbalance could be related to concomittant helminthic infections was supported by several interventions and case-control studies. METHODS AND FINDINGS: We investigated here the hypothesis that the delayed acquisition of immunity to malaria could be related to a worm-induced Th2 drive on antimalarial immune responses. IgG1 to IgG4 responses against 6 different parasite-derived antigens were analyzed in sera from 203 Senegalese children, half carrying intestinal worms, presenting 421 clinical malaria attacks over 51 months. Results show a significant correlation between the occurrence of malaria attacks, worm carriage (particularly that of hookworms) and a decrease in cytophilic IgG1 and IgG3 responses and an increase in non-cytophilic IgG4 response to the merozoite stage protein 3 (MSP3) vaccine candidate. CONCLUSION: The results confirm the association with protection of anti-MSP3 cytophilic responses, confirm in one additional setting that worms increase malaria morbidity and show a Th2 worm-driven pattern of anti-malarial immune responses. They document why large anthelminthic mass treatments may be worth being assessed as malaria control policies