Case Report A Case of Pneumatosis Cytoides Intestinalis Successfully Treated by Inhalation of High Concentration Oxygen JMAJ 48(10): 513–517, 2005 Toshihito Fujii,*1 Makoto Takaoka,*1 Yoshihiro Tagawa,*1 Takahiro Kitano,*1 Mika Ohmiya,*1 Yoshinari Hashimoto,*2 Kazuichi Okazaki*3 Abstract A 44-year-old man was referred to our hospital because of a positive fecal occult blood test. A barium enema study revealed numerous oval-shaped, elevated lesions with smooth surfaces in the region including the ascending colon. He was admitted to our hospital for investigation and therapy. Based on colonoscopic examination, we /5hoursןdiagnosed him as having pneumatosis cytoides intestinalis (PCI). He was treated with oxygen (5L/min day for 14 days) via a nasal cannula. Most of the multiple cysts diminished and some changed into white scars. The simplicity of oxygen therapy supports its use as a first-line treatment. Key words Pneumatosis cystoides interstinalis, High-concentration oxygen inhalation Family history: Not remarkable. Introduction Past exposure: No past exposure to trichloro- ethylene. Pneumatosis cystoides intestinalis (PCI) is a Present illness: The patient was found to be relatively rare condition in which numerous positive for fecal occult blood on a health screen- gas-filled cysts mainly containing nitrogen are ing, and was referred to our hospital for detailed formed within the intestinal wall. While idio- examination. An outpatient barium enema study pathic and secondary cases are known, the latter revealed numerous oval-shaped, elevated lesions may result from exposure to trichloroethylene, with smooth surfaces in the region from the chronic respiratory diseases such as pulmonary hepatic flexure to the ascending colon. The emphysema, and collagen disease. We report patient was hospitalized for investigation and our experience with a case of PCI, which was therapy. detected by workup following a positive fecal Condition at the time of hospitalization: occult blood test, including literature-based Height 165 cm, body weight 67 kg, blood pressure discussion of this disease. 136/74 mmHg, heart rate 72/min, regular pulse, no signs of anemia in palpebral conjunctiva, Case no jaundice in bulbar conjunctiva, no abnormal findings in cardiopulmonary auscultation, no Patient: 44-year-old male. palpable hepatosplenomegaly or masses in the Chief complaint: None. abdomen. Medical history: Not remarkable. Laboratory findings at the time of hospital- *1 Department of Internal Medicine, Kansai Medical University Kouri Hospital, Neyagawa *2 Department of Gastroenterology, Mitsubishi Kobe Hospital, Kobe *3 The Third Department of Internal Medicine, Kansai Medical University, Moriguchi Correspondence to: Toshihito Fujii, Department of Internal Medicine, Kansai Medical University Kouri Hospital, 8-45 Kourihondoricho, Neyagawa, Osaka 572-0082, Japan. Tel: 81-72-832-5321, Fax: 81-72-833-3990, E-mail: [email protected] JMAJ, October 2005 — Vol. 48, No. 10 513 Fujii T, Takaoka M, Tagawa Y, et al. Table 1 Laboratory findings at the time of hospitalization mm3 Na 138mEq/L/104ןRBC 552 Hb 17.0g/dl K 3.8mEq/L Ht 48.5% Cl 100mEq/L mm3 BUN 13.9mg/dl/104ןPlt 18.9 WBC 5280/mm3 Cr 0.91mg/dl TP 7.3g/dL CRP 0.02mg/dl (מ) Alb 4.3/dL Antinuclear antibodies (מ) T.Bil 2.24mg/dL Anti-RNP antibodies (מ) AST 22U/L Anti-Scl-70 antibodies (מ) ALT 31U/L Anti-Jo-1 antibodies ALP 226U/L LAP 127mU/ml PH 7.412 ␥-GTP 17U/LPO2 90.9mmHg CHE 333U/L PCO2 40.0mmHg LDH 135U/LBE 0.9 mmol/l CPK 90U/L SaO2 98.2% Fig. 2 Abdominal CT increase in total bilirubin (2.24). Antinuclear antibodies, anti-RNP antibodies, anti-Scl-70 antibodies, and anti-Jo-1 antibodies were nega- tive. Blood gas analyses were within normal ranges, including pH 7.412, PCO240 mmHg, PO290.9 mmHg, BE 0.9, and SaO2 98.2%. Fig. 1 Abdominal X-ray Abdominal X-ray at the time of hospital- ization (Fig. 1): Aggregation of numerous round- shaped transparencies was seen in the region ization (Table 1): No abnormalities were found from the hepatic flexure to the ascending in general hematology tests. Blood chemistry colon. tests showed no abnormalities except for a slight Abdominal CT at the time of hospitalization 514 JMAJ, October 2005 — Vol. 48, No. 10 PCI SUCCESSFULLY TREATED BY INHALATION OF HIGH CONCENTRATION OXYGEN Fig. 3 Barium enema X-ray Fig. 4 Colon endoscopy (at the time of hospitalization) Fig. 5 Colon endoscopy (day 15) Fig. 6 Colon endoscopy (day 70) (Fig. 2): Although air was depicted in the the patient as having PCI and commenced intestinal wall in the hepatic flexure, no wall intermittent high-concentration oxygen inha- thickening or other signs of inflammation were lation. Oxygen was administered via a nasal seen. cannula at the rate of 5 L/min, 5 hours/day for Barium enema X-ray at the time of hospital- 2 weeks. ization (Fig. 3): Diffusely distributed elevated Colonoscopy on the day after the end of lesions with smooth surfaces were seen in oxygen therapy (Fig. 5): Most of the multiple the region from the hepatic flexure to the cysts had diminished, although some small ascending colon. reddish elevated lesions remained. Colonoscopic findings (Fig. 4): Numerous Colonoscopy 8 weeks after the end of oxygen multiple cysts were seen in the region from the therapy (Fig. 6): Multiple cysts had largely ascending colon to the hepatic flexure. disappeared and only white scars were Based on the above findings, we diagnosed observed. JMAJ, October 2005 — Vol. 48, No. 10 515 Fujii T, Takaoka M, Tagawa Y, et al. a high occurrence of PCI among persons Discussion chronically exposed to trichloroethylene and the detection of trichloroethylene in the gas-filled PCI was first described by Du Vernoi in 1730.1 cysts. In addition, there have been reports of PCI The first report of this disease in Japan was made accompanying collagen disease such as systemic by Miwa in 1901,2 and according to Matsuoka scleroderma.13 Because our case had no history et al.,3 there were 509 cases reported by 1997. of surgery or trauma, showed no abnormality in Although it was previously considered to occur chest X-ray and blood gas analyses, and lacked a preferentially in the ileum,4 recent reports sug- history of exposure to trichloroethylene, we gest a high occurrence in the large intestine, considered that this case was idiopathic. in particular the sigmoid colon.5 While older It is difficult to diagnose PCI solely based on reports indicated higher prevalence in males clinical symptoms, but a physician with the than females, recent cases include more females knowledge of this disease can relatively easily than males.6 No symptoms specific to PCI identify this disease based on the findings from are known. Cases involving the small intestine abdominal X-ray, barium enema X-ray, and often show abdominal distention, abdominal endoscopy. PCI most frequently develops in the pain, and flatulence, while those involving the subserous tissues of the intestines, followed by large intestine usually present bloody mucous submucous tissues, and the development of PCI stool, melena, and diarrhea.7 within the muscular layer is considered rare.14 The entity of PCI is the presence of gas-filled In cases where the gas-filled cysts are located cysts in intestinal walls. An overwhelming predominantly in the submucous layer, abdominal majority of PCI cases have some underlying X-ray depicts numerous oval-shaped bubbles of disease, as 15% of all cases are idiopathic and various sizes like bunches of grapes along the 85% are secondary to underlying disease.4 intestinal wall, and barium enema study reveals The etiology of PCI has not been well clarified. multiple filling defects resembling holly leaves.15 Bacterial, mechanical, and chemical mechanisms If there are gas-filled cysts in the subserous layer, have been proposed. The bacterial theory lesions are identified as froth-like clustering of depends on the fact that necrotizing enterocolitis small transparencies or linear transparencies in children is often complicated with PCI. along the outer perimeter of the intestines.16 It presumes that the gas-generating bacteria in PCI can be treated either with surgical the intestines invade into the intestinal wall and removal or with a conservative method using form cysts.8 However, the bacterial theory seems oxygen inhalation. According to the compilation to be disproved by the fact that gas-generating by Sakashita et al.,17 surgery has been selected bacteria mainly produce hydrogen and methane, for the cases showing severe melena and other while the gas in PCI lesions consists of 90% symptoms, cases with suspected digestive tract nitrogen.9 At present, the mechanical theory perforation due to pneumoperitoneum, cases is considered plausible. There are 2 possible developing ileus, cases in which malignancy mechanical processes causing PCI. One is the could not be ruled out, and cases that actually mechanism depending on intestinal factors, developed digestive tract perforation. With where the elevation of pressure in the intestinal respect to oxygen therapy, Forgacs18 reported lumen due to intestinal obstruction, surgery, successful disappearance of pneumatosis after endoscopy, or trauma is considered to cause continuous inhalation of 75% high-concentration infiltration of intestinal gas through minute oxygen for 6 days in 1973. In Japan, Daitoku et cracks in the mucosa.10 The other possibility, al.19 reported the effectiveness of this therapy in assuming the causal involvement of the lungs, 1980, followed by reports of high-concentration is that painless rupture of pulmonary alveolar oxygen therapy using a non-breathing face mask walls may develop in such conditions as chronic and nasal catheter, high-pressure oxygen therapy, obstructive pulmonary disease and the gas may and a number of other methods. The mechanism enter the intestinal walls via the mediastinum, of this treatment has been explained as follows: retroperitoneal tissues, and the tissues around Because the gas in the cysts mainly consists of mesenteric arteries.11 With respect to the nitrogen, the elevation of arterial oxygen partial chemical theory, Yamaguchi et al.12 reported pressure caused by high-concentration oxygen 516 JMAJ, October 2005 — Vol.