All are true regarding typhoid fever, except -
Typhoid fever Clinical features are outlined in Box 11.42. The incubation period is typically about 10-14 days but can be longer, and the onset may be insidious. The temperature rises in a stepladder fashion for 4 or 5 days with malaise, increasing headache, drowsiness and aching in the limbs. Constipation may be caused by swelling of lymphoid tissue around the ileocaecal junction . In children diarrhoea and vomiting may be prominent early in the illness. The pulse is often slower than would be expected from the height of the temperature, i.e. a relative bradycardia. At the end of the first week, a rash may appear on the upper abdomen and on the back as sparse, slightly raised, rose-red spots, which fade on pressure. It is usually visible only on white skin. Cough and epistaxis occur. Around the 7th-10thday, the spleen becomes palpable. Constipation is followed by diarrhoea and abdominal distension with tenderness. Bronchitis and delirium may develop. If untreated, by the end of the second week the patient may be profoundly ill. Paratyphoid fever The course tends to be shoer and milder than that of typhoid fever and the onset is often more abrupt with acute enteritis. The rash may be more abundant and the intestinal complications less frequent. Complications Haemorrhage from, or a perforation of, the ulcerated Peyer's patches may occur at the end of the second week or during the third week of the illness. A drop in temperature to normal or subnormal levels may be falsely reassuring in patients with intestinal haemorrhage. Additional complications may involve almost any viscus or system because of the bacteraemia present during the first week. Bone and joint infection is common in children with sickle-cell disease. Investigations In the first week, diagnosis may be difficult because, in this invasive stage with bacteraemia, the symptoms are those of a generalised infection without localising features. Typically, there is a leucopenia. Blood culture establishes the diagnosis and multiple cultures increase the yield. Stool cultures are often positive in the second and third weeks. The Widal test detects antibodies to the O and H antigens but is not specific. Management Antibiotic therapy must be guided by in vitro sensitivity testing. Chloramphenicol (500 mg 4 times daily), ampicillin (750 mg 4 times daily) and co-trimoxazole (2 tablets or IV equivalent twice daily) are losing their effect due to resistance in many areas of the world, especially India and South-east Asia. Fluoroquinolones are the drugs of choice (e.g. ciprofloxacin 500 mg twice daily), if nalidixic acid screening predicts susceptibility, but resistance is common, especially in the Indian subcontinent and also in the UK. Extended-spectrum cephalosporins (ceftriaxone and cefotaxime) are useful alternatives but have a slightly increased . Ref Harrison20th edition pg 980
Peak incidence 30-50 years
No non human reservoir
Carriers for years
Life long immunity carmot be acquired
Infection