No abstract

Arterial thrombosis occurs with increased frequency in cigarette smokers. It is believed that disturbance of platelet function, especially aggregation, is the essential mechanism responsible for this pathology. However, the effect of smoking on the quantity of platelets might be another contributing factor. The effect of smoking on platelet count is still controversial. We performed a cross section-al study to compare the platelet count and platelet parameters in Thai police who are smokers and non-smokers. A total of 30 Thai police in Bangkok were included in this study. Of the 30 police, there are 5 non-smokers and 25 smokers. The platelet counts and platelet parameters of the subjects were not significantly different between smokers and non-smokers.

Hookworm is an important intestinal parasite infection with high prevalence in tropical countries. In addition to iron deficiency anaemia, the human hookworm appears to have evolved a number of complementary strategies to overcome the host's haemostatic processes. These include the inhibition of blood coagulation, platelet aggregation and mediator release, and the secretion of fibrinogenolytic enzymes. In this work, we studied the platelets in the subjects with detection of hookworm infection from screening stool examination comparing to those without. One hundred subjects were included, studied for stool parasite and platelet parameters. Of our 100 subjects, hookworms were identified in stools of six cases, giving an infection rate equal to 6%. The platelet parameters of the subjects showed a statistically significant lowering of mean platelet volume (MPV) in the subjects with hookworm infection. Also, we detected a non-significant lower platelet count in subjects with hookworm infections. Of interest, the alteration in platelet size, identified by platelet parameters, has never been documented in the literature. This observation might be a pathological process or might be an accidental finding in our study.

Lead is an important toxic metal found in industrial communities. Due to the industrialization in the recent decade in Thailand, lead intoxication as a toxicant-related disorder becomes a new public health problem. A retrospective study on clinical presentation of hospitalized patients with diagnosis of lead intoxication during year 1990-1999 in King Chulalongkorn Memorial hospital, the largest Thai Red Cross Society Hospital, was performed. All 14 cases diagnosed with lead intoxication were identified in our series. Average age of the subjects was 25.55 +/- 21.93 years old. Male predominance was detected in our series (male:female = 12:2). Two main groups of subjects as; (1) childhood aged below 10 years old (male:female = 4:2) and (2) adult aged between 24 and 60 years old (n = 8, all male), can be identified. For the first group, the clinical presentations were convulsion (n = 3), unexplained anemia (n = 1), attention deficit (n = 1) and asymptomatic (n = 1), respectively. All of the subjects in this group presented the history of living at the old battery plant area. Five of the six cases came from the same village. For the second group, the clinical presentations were unexplained abdominal pain (n = 5), chronic renal failure (n = 1), unexplained anemia (n = 1) and asymptomatic (n = 1), respectively. Most of the subjects (75%) in this group presented the history of working in the battery plant for more than 10 years. Another case presented the history of gunshot and residual bullet in the bone marrow. The other one left is an interesting case with the history of prolonged usage of ritual pill and holy paper incineration. Like other studies, battery plant had strong relation with the lead intoxication. Although the total identified cases are rather few, there may be more undetected asymptomatic lead intoxication cases in the community. Specific control of lead resulted from battery plant and monitoring of the workers as public health strategies are still recommended.

Smoking has contributed to various neurological, cardiovascular, and pulmonary diseases. According to carcinogens found in cigarette smog, benzene is one of the important carcinogenic compounds. The urinary trans, trans-muconic acid (ttMA) levels among a sample of 10 Thai smokers and 35 Thai non-smokers were investigated, compared and reported. The average urinary ttMA level in smokers and non-smokers were 2.19 +/- 2.32 and 0.24 +/- 0.33 mg/gCr, respectively. A significant higher urinary ttMA level among the smokers was observed (P < 0.05). Since the higher urinary ttMA indicates the higher occult risk for cancer, the usage of urinary ttMA is recommended as a monitoring tool to follow up benzene exposure in the smokers.

Benzene is of particular concern because of recent research indicating that benzene exposure can result in toxicity. The hematotoxic effect of benzene is mentioned. However, there is little knowledge about the correlation between the biomarker of benzene exposure and changes in red blood cell parameters. Here, the correlation between the urine trans, trans-muconic acid (ttMA) level and red blood cell parameters were studied in 30 Thai subjects at risk. The regression analysis shows no significant correlation between urine ttMA and any studied red cell parameters (Hb, MCV or MCH). Based on our hematologic data, we proposed that only investigation for the urine ttMA might be not sufficient in detection of alteration in red blood cell parameters in the exposed population. Combinations between biomarker and hematological test are recommended.

Although patients with cirrhosis of the liver show relative immunosuppression and therefore have increased susceptibility to most infections, they rarely develop liver abscesses. In a retrospective case review, the pathogens causing the liver abscesses observed, between January 1992 and December 2001 at the King Chulalongkorn Memorial Hospital, Bangkok, Thailand, in 44 hospitalized patients diagnosed as cases of liver cirrhosis were investigated. The most common clinical symptoms and signs of the abscesses--abdominal pain (80%), fever and chills (73%), and abdominal tenderness (73%)--were similar to those seen in non-cirrhotic patients with abscesses. The frequency of liver abscess among the cirrhotic patients was low (0.46%). Most (71%) of the abscesses were in the right lobe and most (71%) of those with abscesses only had a single abscess. Surprisingly, many of the abscesses (36%) were apparently caused by amoebae. Bacterial pathogens were identified in eight patients (18%) by blood culture and 15 (34%) patients by pus culture. Seven (16%) of the blood cultures and 13 (30%) of the pus contained Gram-negative aerobes, indicating that such pathogens, particularly Klebsiella pneumoniae (in six pus and six blood cultures) and Escherichia coli (in three pus cultures and one blood), were the most common causes of the bacterial abscesses. Pus culture appeared more successful than blood culture for bacterial abscesses, and amoebic abscesses could always be identified by direct microscopical examination of pus samples. Aspiration of liver abscesses, to obtain pus samples for culture and microscopy, is therefore recommended.

The green pit viper (Trimeresurus albolabris and Trimeresurus macrops) is a common venomous snake in Thailand. The green pit viper venom has major effects on the hematologic system. The venom is found to have a thrombin-like effect in vitro but cause a defibrination syndrome in vivo. Unlike other pit viper snakes (such as Malayan pit viper and Russel's pit viper), the venomous effect on red blood cells is rarely mentioned. Clinical features of venomous snake bites vary from asymptomatic to fatal bleeding. In this study, an attempt was made to discern hematologic parameters in green pit viper envenomation and to characterize the changes in blood cells. The study included data from 40 patients who were hospitalized at the King Chulalongkorn Memorial Hospital during 1995 to 1999 and 40 normal, healthy subjects as control. Concerning platelet determination, significantly decreased (p < 0.05) total platelet count and mean platelet volume (MPV) were demonstrated in envenomous blood. The changes in blood cells may be partly due to the effect of green pit viper toxin on the platelet morphology. However, the explanation of this phenomenon requires further investigation for the specific pathophysiology. The components of green pit viper venom that have these hematologic effects in humans are interesting and should be further identified.