Rapid Responses to:
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Rapid Responses: Rapid Responses published:
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Fever of unknown origin: case presentation
- Martin P. Grecco (1 September 2006)
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PUO
- ER McRorie (2 September 2006)
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Re: Fever of unknown origin: case presentation
- Brian Payne (2 September 2006)
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The search for a diagnosis.
- Anjay M A Pillai (2 September 2006)
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Re: Fever of unknown origin: case presentation
- Mark L Anderson (2 September 2006)
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subacute bacterial endocarditis
- charles h davis (2 September 2006)
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Re: Re: Fever of unknown origin: case presentation
- Nazar R DESSOUKI (3 September 2006)
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Immune complex disease
- Deepak Kejariwal (3 September 2006)
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Re: The search for a diagnosis.
- ANTHONY CHURCHER (3 September 2006)
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Rheumatology or Infectious disease issue..
- Marin Marinovic (3 September 2006)
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PUO
- John P McCormack (3 September 2006)
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PUO
- Jim Mathew Kocheril (4 September 2006)
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PUO with low complement
- Amit Patel (4 September 2006)
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Fever of unknown origin: I still don’t have clear diagnosis
- Maria Belechri (4 September 2006)
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Computer Diagnosis
- Michael D Innis (5 September 2006)
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Consent
- Anne Holmes (5 September 2006)
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Fever of unknown origin: surely adult onset Still's
- Stuart N Cohen (6 September 2006)
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interactive case report
- Hilary Wilson (6 September 2006)
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PUO - In Young Girl
- Srinath Meadipudi (6 September 2006)
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puo
- vivek rajagopal (6 September 2006)
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PUO
- David Mitchell (7 September 2006)
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Re: PUO
- David Mitchell (8 September 2006)
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Martin P. Grecco, Intern- Internal Medicine Fernandez Hospital, Cerviño 3356 Buenos Aires, Argentina
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1) What we have here is a young patient with fever, rash, articular features and some lab features like hypocomplementemia, leukocytosis and abnormal liver function tests; and the rest of it is normal. In this case I think one should consider: *Still disease (clinical pattern compatible, negative serological
tests)
Among these, I think the most probable diagnosis is Systemic juvenile arthritis. I have known cases like these, a young person with fever, one single joint affected, rash that waxes and wanes with fever spikes. It is also known that Still disease can produce mild liver test abnormalities, elevated C reactive protein with negative ANA and RF. Mostly all of the infectious etiologies have been excluded. Honestly, I don´t have a good explanation for the hypocomplementemia. 2)I would like to repeat the rheumathological panel, but I think that all the important test have been done. 3)I would emphasize that most of the important and treatable conditions have been excluded, and that if all test are normal, it´s quite possible that the patient has Still disease, which is a diagnosis of exclusion. So I think it´s important to reassure the patient and family that perhaps more time is needed to establish a diagnosis. Competing interests: None declared |
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ER McRorie, Consultant Rheumatologist Rheumatic Diseases Unit, Western General Hospital, Edinburgh. EH4 2XU
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1. The differential diagnosis should include adult-onset Still's disease (AOSD) (this is the most likely diagnosis, though doesn't easily explain the hypocomplememtaemia), occult lymphoma (or other neoplasm), and occult infection. 2. Check serum ferritin - typically very high in AOSD eg ~10,000 ug/l ie higher than you would expect as an acute-phase reactant. Also v high in macrophage activation syndrome (tho might expect leucopenia) and obviously haemochromatosis (but clinical picture not suggestive). If unhelpful, CT chest/abdo/pelvis. If necessary, stop antibiotics and reculture. 3. I would try and explain the reasons for the diagnostic uncertainty, and which diagnoses are less likely given the results of investigations to date. I would say that a systemic inflammatory illness was top of my list of likely diagnoses but that if serum ferritin was unhelpful, then further imaging would be necessary to look for an alternative explanation. Competing interests: None declared |
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Brian Payne, retired consultant geriatrician Norwich NR4 6AE, UK
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One classical cause of PUO from the Mediterranean area not yet excluded is typhoid/paratyphoid, and the appropriate serology is needed. The initial antibiotics would probably render blood cultures falsely negative and the rash could well be simply drug-associated. A history of mosquito bites is probably a red herring as malaria is now very unusual in Italy and the syptoms/signs are not those of more recent exotic diagnoses such as viral haemorrhagic or encephalitic fevers. Competing interests: None declared |
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Anjay M A Pillai, Research Fellow, Paediatrics Airedale General Hospital, Steeton, Keighley, West Yorkshire BD20 6TD
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In essence this is a 19 year old girl with: Persistent fever, transient rash and monoarthralgia. Elevated acute phase reactants ( C-Reactive Protein, Neutrophilia). Raised Gamma Glutamyl Transferase(GGT) with otherwise normal liver function. Low complement levels. Differential Diagnosis: Running this across the classical diagnostic sieve: 1. Infection: Most of the common infections have been ruled out. Others that could be considered include: • Tuberculosis: not a typical clinical picture and no h/o contact , but needs to be considered. • A mild case of “chronic” meningococcemia cant be ruled out, although 3 weeks is long enough for the disease to either worsen or resolve • Rubella: fever, rash and arthralgia , but rash not typical .Prolonged fever unlikely. • Hepatitis/Cholangitis; could explain fever and elevated GGT, but no abdominal symptoms or jaundice. • Some cases of Enteric fever may not have positive blood cultures. Other “exotic” infections don’t seem to fit the bill. 2. Connective tissue/auto-immune disease: • Juvenile Rheumatoid Arthritis is a strong possibility. The evanescent rash is typical. However conventional wisdom dictates that when there is rash, there is usually polyarthralgia. • Systemic Lupus Erythematosus(SLE): Also a strong contender. The altered liver function and the low complement levels are consistent with SLE. • Auto-immune Hepatitis • Sclerosing cholangitis: can explain fever and altered GGT. 3. Immune deficiency: Possible coagulase-negative staphylococcal sepsis in association with low complement levels warrant further testing. 4.. Maligancies: Hodgkins and pre-leukaemic leukaemia can present like this with a normal blood film as can some renal tumours 5. Endocrine: Thyrotoxicosis should be considered in view of tachycardia. Can be associated with auto-immune diseases 6.. Others: Familial Mediterranean fever Juvenile Rheumatoid Arthritis (Systemic Onset) and SLE are highest on the list of possibilities. Further investigations: 1. ESR
What to tell the patient/parents This is obviously a distressing time for the patient and her parents. I would tell them that many of the common causes of fever have been ruled out and that we are giving her adequate antibiotic cover for most of the bacteria. We might need to do more specialised tests to find out the exact cause. As always this is more likely to be an uncommon presentation of a common disease than vice versa. If all tests are negative, a bone marrow aspiration may have to be considered. Possibility of occult malignancy, though frightening has to be mentioned. Competing interests: None declared |
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Mark L Anderson, SpR Paediatrics Queen's Medical Centre, Nottingham, NG7 2UH
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The definite features here are:
Differential diagnosis of fever of unknown origin can be divided
into:
In terms of infection, the pretreatment with antibiotics makes culture results difficult to interpret, but most things have already been considered. One would have to think about TB and HIV, but neither of these would explain the complement levels. I note there are no urine culture results. Malignancy must be considered, but imaging is all normal and this wouldn't explain the complement levels either. The low complement levels suggest complement activation which therefore makes a rheumatological cause seem most likely. Autoantibody screen is negative which rules out most common things, but returning to the history this episode was preceded by a sore throat, which makes a post -streptococcal syndrome a strong possibility. ASOT can be negative in these cases early on and therefore might be worth repeating. The addition of an anti-DNAse B or anti-hyaluronidase test might be of use. Urinalysis might also be of use. Even if all tests were negative, the prognosis is frequently good, as far as I am aware. Competing interests: None declared |
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charles h davis, cons neurosurgeon preston pr29ht
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if in doubt sbe, stop antiobiotics, repeat echos Competing interests: None declared |
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Nazar R DESSOUKI, consultant surgeon ST BERNARDS HOSPITAL GIBRALTAR
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Patients with FUO are elusive and challenging clinical cases. FUO is an illness of greater than 3 week's duration. Fever higher than 38.3oC on several occasions. No diagnosis established despite 1 week of intensive evaluation. Common causes:
A thorough history is very important. This history should include information concerning alcohol consumption, medications, occupational history, pets, travel, familial disorders, and previous illnesses. Examples of diseases for which clues are provided include:
Prior inflammatory processes in the abdomen can lead to intraabdominal abscesses- patient with Crohn's disease or prior episode with cholecystitis, diverticulitis, or appendicitis. Comprehensive History Repeated Physical Examinations
Further evaluation of any abnormalities detected by above tests. Competing interests: None declared |
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Deepak Kejariwal, SpR, Gastroenterology Norfolk & Norwich University Hospital
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19 F with fever, raised inflammatory markers and hypocomplementemia- Differential diagnosis here are- 1. Immune complex disease- SLE or glomerulonephritis
Investigations suggested-
Obviously distressing time for everyone but would not discuss cancer at this stage. Competing interests: None declared |
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ANTHONY CHURCHER, RETIRED single handed GP Eastbourne BN22 9QN
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1/ Dengue Fever is diagnosis
2/ detection of specific antibodies
3/She is well on way to recovery which will be complete leaving no after effects. Full recovery often takes 6 months and can by accompanied with depression. Natural that family feel frustrated since they need a specific doctor for help, encouragement and supervision. No aspirin or non-steroidal inflammatory drugs since bleeding tendency. US use guaiac test for occult blood. Mussolini banished malaria from Italy by drainage of extensive swamps. A remarkable feat but global warming has brought the mosquito back. World maps do not show the return but the shape does not allow vivid illumination Competing interests: None declared |
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Marin Marinovic, Family Physician/Emergency physician SKMC,Abu Dhabi,UAE
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1.What differential diagnoses would you consider ? A/ Still's disease, adult type/most probable diagnosis/ B/ Osteomyelitis /less likely/ C/ Another collagen disease /less likely/ D/ Malignancy /highly unlikely, thank God/ 2. What further investigations should be carried out ? It seems to me that this young lady has been thoroughly and meticuously investigated. There are not many, if at all any test(s) that have not been done. Looking at the all the investigations ordered and done, she was probably initially admitted under Infectious Disease team. They did rule out most of the infective causes. It must be probably them who started IV antibiotic treatment on the background of what was initially looking as a positive blood culture. Most of other potential causes (malignancy, collagen vascular disease) have been almost ruled out as well. Internal Medicine team seems to be very good and well coordinated in that hospital. I have feeling that Rheumatology team made important input to the final diagnosis for this young lady. The only test that I would consider adding is X-ray of the right knee joint and distal femur. Just to rule out osteomyelitis or any other unexpected joint/bone problem in that area that is already clinically tender. ESR will definitely be high and I would not be pushing very hard for it. I do not think joint aspiration is necessary. 3. What would you tell the patient and her parents given that tests have not revealed a clear diagnosis at this stage ? I would tell them that at this stage the definitive diagnosis is not clear yet. However, their daughter may be having rare type of disease called Still's disease. But before we definitely confirm it as a such (this is diagnosed after other disease are excluded), it is important to get joint opinion from Rheumatology and Infectious Disease team. The answer is probably somewhere there.... Competing interests: None declared |
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John P McCormack, GP Rosmuc, Connemara, Ireland
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I agree with all of the above and that the rash is most likely a drug
eruption. Top
of my list for next Ix is
The hardest thing to cope with from both physician and family point of view is that after all Ix have been completed there still may be no answer and the diagnosis may finally end up as being Pyrexia of UNKNOWN Origin. At what stage do we decide to stop doing tests? I have mixed emotions as my heart goes out to this unfortunate young woman and her family but my head loves a puzzle and I will follow progress with much interest. Competing interests: None declared |
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Jim Mathew Kocheril, clinical fellow - medicine Princess of Wales hospital, bridgend, CF31 1RQ
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The following would be my diffrential diagnosis, in the order of priority. 1) Still's disease (young girl, spiking fever, arthralgia, neutrophilia, negative antibodies). Very high serum ferritn would be complementary. After ruling out infection a trial of steroids after discussion with the family. 2) I would rule out osteomyelitis by considering MRI of the knee joint and femur / white cell scan, especially in view of neutrophilic leucocytosis, staphylococcus in blood culture and knee tenderness before starting steroid trial. 3) I would do ultrasound of abdomen /CT abdomen to rule out occult collection, adenopathy or hepatosplenomegaly. 4) Auto immune processs is my last consideration and therefore if the liver abnormalities are persistent liver biopsy. Competing interests: None declared |
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Amit Patel, Senior House Officer in Cardiology The Heart Hospital (UCLH NHS Foundation Trust), 16-18 Westmoreland Street, London, W1G 8PH, UK
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Very briefly, a young female, with a three week history of high fevers, a previous sore throat, a rash, single joint involvement with constitutional upset, an inflammatory response associated with low C3 greater than low C4, neutrophilia, slightly deranged liver enzymes and a travel history. Differential diagnosis and further investigations include:
Other things to exclude include sarcoidosis (calcium, urine calcium, ACE), TB (special TB blood cultures, Mantaux, Heaf), HIV (PCR, serology), Dengue (serology), syphilis (VRDL). Unlikely rarities include familial Mediterranean fever, hyperimmunoglobulin D syndrome (high IgD and IgA) and familial Hibernian fever. The results of more basic tests: Renal function?
Family discussions I would explicitly discuss the problem with the patient and her family, making clear the results of all the investigations and the rationale for further tests. The fact that everything that can be done is being done should be reiterated. The fact that a clear diagnosis at this stage has not been achieved should also be stated but that antibiotics will continue for the time being to cover infective endocarditis. Competing interests: None declared |
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Maria Belechri, SHO Medicine Hull and East Yorkshire NHS Hospitals
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1) Although is an exclusion diagnosis, adult Still’s disease is suggested by the fever pattern, sore throat and the classic non pruritic rash that appears when fever spikes. In this variant of rheumatoid arthritis joint symptoms might be mild or absent in the beginning. Leukocytosis is a rule and most adults are in their 20s or 30s. 2) Regarding further investigations I would request serum ferritin levels as they are exceptionally high in adult Still’s disease. 3) I would explain to the family that most of the treatable conditions have been ruled out but there is no clear diagnosis at this stage. The diagnosis of adult Still’s disease is likely but as it is an exclusion diagnosis, further investigations are required. Competing interests: None declared |
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Michael D Innis, Director Medisets International Home 4575
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Results of laboratory investigations 1.Neutrophilia 2.C reactive protein > 60 mg/l 3.Liver function tests:AST > ALT 4.C3 Low 5.C4 Low Entered into Computer Diagnosis: Lyme Disease Differential Diagnosis - Nil Further Investigations Unnesessary IFA / ELISA Competing interests: Computer diagnosis |
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Anne Holmes, General Practitioner Tithebarn Medical Centre, Stockton on Tees, TS19 8RH
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I would remember that this patient is an adult and not tell her parents anything without her informed consent. Competing interests: None declared |
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Stuart N Cohen, SpR in Dermatology Queen's Medical Centre, Derby Road, Nottingham, NG7 2UH
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Surely the diagnosis is adult onset Still's disease. The typical features of high-grade swinging fever, fleeting macular rash and arthralgia are present. These occur in 95.7%, 51-87% and 64-100% of cases respectively. Myalgia, present in 56-84% and elevated liver enzymes, present in 50-75% of cases, also feature. Sore throat also fits with the diagnosis. More detail on the rash, which is often characteristic, and the frequency and regularity of the fever would be helpful. The problem lies in the absence of a diagnostic test. Ferritin and, in particular, glycosylated ferritin have been suggested: in health, 50- 80% of ferritin is glycosylated -- this falls to 20-50% in inflammatory diseases and is often less than 20% in adult onset Still's disease. These should be checked if possible. From the results available, infection seems highly unlikely, as does an alternative inflammatory diagnosis. Lymphoma may not be impossible, though absence of lymphadenopathy on examination, chest radiograph and abdominal ultrasonography, with the strikingly high C reactive protein, essentially exclude this possibility, given that typical features of an alternative diagnosis are present. Treatment options include non-steroidal anti-inflammatory drugs, corticosteroids, other immunosuppressives or anti-rheumatics, intravenous immunoglobulin and biological therapies including etanercept, infliximab and others. I would favour a trial of corticosteroids (perhaps pulsed methylprednisolone) and/or methotrexate in the first instance. The patient (and, if she wishes, her parents) should be given information on the diagnosis; the concepts of diagnosis of exclusion and therapeutic trial must be explained. Their frustration is completely understandable and time should be spent on explaining the need for the numerous, apparently unhelpful yet crucial investigations. Reference: Efthimiou P, Paik PK, Bielory L. Diagnosis and management of adult onset Still's disease. Ann Rheum Dis 2006; 65:564-72 Competing interests: None declared |
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Hilary Wilson, Consultant rheumatologist Glasgow G12 9EQ
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1 Still's disease 2 Urea and electrolytes Urinalysis and MSSU Culture any Synovvial fluid from the knee Stop antibiotics and re culture TB cultures 3 Explain that investigations thus far have been reassuring and that it can take time to figure out the cause of pyrexia Competing interests: None declared |
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Srinath Meadipudi, Staff Grade Woodend Hospital,Aberdeen,AB15 6XS
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In brief a young girl presenting with a H/O sore throat, rash appearing with spiking fever, abnormal LFTs (Colestatic Picture), Large joint tenderness, raised inflammatory markers, Low C3 and Normal Autoantibody screen. Diagnosis to be considered
Competing interests: None declared |
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vivek rajagopal, spr salisbury, po15 7ne
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the differential in this case is either infection or inflammatory conditions.malignancy is unlikely as crp's of that magnitude are rarely seen in malignancy presenting with fever.the 2 inflammatory conditions that can present with fever and crp > 300 are adult onset stills disease or vasculitis.negative ANCA can be seen in upto 50% of microscopic polyangitis,30% of churg strauss and 10-20% of wegener's. the way forward is to repeat immunology and get a biopsy if other manifestations such as peripheral neuropathy or skin lesions develop.cholangitis and hepatic abscesses are other 2 possibilities in view of the abnormal lfts. a ct scan chest,abdo and pelvis would exclude a pus collection, to summarize investigations at this stage: ferretin levels, ct chest abdo pelvis. Competing interests: None declared |
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David Mitchell, Deptarment of Microbioloy Trinity College Dublin
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This is an interesting problem. Given that a rheumatologist is involved here a rheumatological problem seems likely to be the ultimate diagnosis with Still's disease topping the list. Putting this possibility aside for the moment and treating this as a PUO lets consider the remaining possibilities. One aspect of the case that is curious is the repeated films for malaria. Italy isnt well known for malaria. This was eradicated form Italy after the Second World War so perhaps some travel history was ommited here? Alternatively the doctors here did this investigation simply to 'rule it out.' PCR is a lot more sensitive than thin & thick films but I dont think this is worth doing here. In a non immune person with P falciparum would be a lot sicker than described here. The other species are less widespread and the pattern doesnt fit anyway. Continuing on this theme other parasites might cause a similar pattern here: specifically leishmania. This does occur in this region. This can cause most of the symptoms here - Im not sure about the sore throat. This would fit with the history of insect bites. This can be diagnosed by periferal white cell concentration, urine anitgen detection, serum antibody, bone marrow microscopy and culture depending on availability and local expertese. If the young woman has actually been outside Europe then faecal examination for parasites might be helpful. About 1/3 travelers return with unwelcome guests that are not always symptomatic initially. Most of the other parastic infections should have been ruled out by the blood films: not all I grant you but without a travel history these would in all likelihood be negative. Considering this as a culture negative endocarditis I notice the absense of a Coxiella or ricketisa serology in the list. Again this is compatable with the history of insect bites. This can be done on the blood sample taken already. Borellia is a possibility given the history of bites. Not very 'typical' but many cases are not. The ticks are widespread and the condition very underdiagnosed. Tuberculosis is always a possibility in a PUO. It may be found in the sputum even with a normal chest X ray. The Mantoux or Heaf is sadly not as reliable as many would like to think. Sputum - if necessary induced - should be sent to the lab for public heath reasons as much as diagnostic. A set of early morning urines is probably worth sending also. On the story given tuberculosis does not seem very likely but these are always worth doing as the public heath implications may be serious. Typhoid is a possibility if the travel history is incomplete here. A test for antibody to the Vi antigen could be done. Faeces culture does not seem to have been done. This possibility is unlikely if the travel history is correct. Dengue has been suggested earlier here. Italy is not known for dengue. Antibodies have been reported in the Italian population to Dengue virus at a low frequency but this may be a cross reaction to one of the other arboviruses. The clinical pattern is not right for dengue so I think this is unlikely. The pattern is not right for most of the recognised arboviruses (>200) but an antibody test for the group antigen might be worth doing in view of the history of bites. Considering the more typical organisms there is no mention of a knee X ray. This I found curious as osteomyelitis is a possibility. The knee is a typical site. Blood cultures may or may not be positive especially if antibiotics have been given. In spite of the presence of penicillinase in the culture media results are not great. The usual suspect here are Stapholococcus aureus. Bone biopsy may be necessary but in the absense of any radiolocal information this would not be indicated. HIV seems to have been considered here. This would be a little unusual for a seroconversion reaction but the pattern is very variable. If the history is credible then this seems unlikely. There is no note of recent blood transfusions, dental work or other methods of known transmission so while this seems unlikely it cannot yet be completely discarded. One further site seems to have remained unexamined: the pelvis. Pelvic inflamatory disease can be an over looked source for a PUO. There is no mention of this examination in the record. Having considered most of the infectious possibilities the question now turns to the other potential causes. This looks like a granulomatous disease. Tuberculosis and fungal infection are typical infectious causes. Non infectious cases include as noted earlier sarcoid. An ACE level seems indicated. This is not 100% sensitive. A CT of the thorax might be helpful. Lymphoma is a possibility. Again a CT thorax would help there. It might be worth extending this to the abdomen depending on how fat or thin the patient is and how good the radiology department is with the ultrasound. The para aortic nodes may difficult to see in fat patients. A bone marrow may be helpful but I would prefer a CT thorax before doing a marrow. Crohns disease may produce most of the findings here. I have seen it present without abdominal pain or diarhoea. I emphasise this is a rare presentation of Crohns disease. I dont think this is likely here but a small bowel follow though might reveal something in a similar case. After this we are into the unusual rheumatological diseases with conditions such as Wegner's and others springing to mind. The negative anti nuclear antibody (and associated antibodies) do not rule out SLE entirely but do make it very unlikely. Given that the case is being presented by a rheumatologist I wont embarass myself any further in this catagory of possibilities. Competing interests: None declared |
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David Mitchell, Department of Microbiology Trinity College, Dublin
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Another possibility not included above is cryptococcus. This is found in Italy but as a clinical problem is uncommon outside those with occupational exposure or those who chose to go down caves. It would be expected to present as chest infection mimicing tuberculosis but like tuberculosis it too may show protean manifestations. It can cause bone destruction - raising agai n the question of why the knee X ray was omitted from the report. Culture of this organism is routine labs is not recommended which reduces the sensitivity of specimens submitted for investigation. It will bind C3 on its capsule and a variable fever is common. The presentation here is unlikely to be due to cryptococcus - absent a history of investigating caves or similar exposure - but I am including it here for completeness. Histoplasmosis does occur in Italy but rarely. Diagnosis is by serology or microscopy. Blastomyces dermatitidis has been reported in Italy but remains very rare. Whipple's disease (due to Tropheryma whippelii) can cause similar symptoms but it would be very unlikely in the absense of diarhoea and the short duration of the condition. 'Atypical' mycobacteria may cause a PUO. These would be expected to present with enlarged lymph nodes somewhere. The chest X ray is not very sensitive for enlarged lymph nodes: a thorasic CT would be helpful. Hantavirus infection has been reported in Italy. While the clincal spectrum of this infection is variable this seems improbable here. Listeria monocytogenes may cause a PUO. While it it often considered in pregnancy it also infects non pregnant persons. If this was the cause it should have shown up in the blood cultures so this possibility is very unlikely. Another possible cause here would be cat scratch fever due to Bartonella henselae. This is a gram negative bacterium that can cause along with others of the same genus 'culture negative' endocarditis. It is transmissible by cat fleas as well as by cat bites or scratches particularly by kittens. Diagnosis is by serology or PCR: PCR has a greater sensitivity but considerably greater cost. An unlikely but possible cause is endocarditis due to organisms of the HACEK group - Haemophilus species (H parainfluenzae, H aphrophilus, and H paraphrophilus), Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and Kingella species. These are a set of gram negative bacteria that may be very difficult to isolate in a laboratory even in the presence of florid endocarditis. They are generally oral/oropharangeal flora and tend to be diagnosed with large vegitations possibly because of their relatively indolent course of infection. Microbiology labs are aware of this possibility: given the absense of vegitations and the apparently negative blood cultures here this diagnosis is unlikely. In a similar vein ehrlichiosis while rare in humans can cause culture negative endocarditis. Diagnosis is by serology. I would consider this unlikely. An unlikely cause unless the travel history is incomplete is melioidosis. This has been reported in zoo workers in countries that are regarded as being free from it. A rare infectious condition that has been associated with PUO is spontaneous abdominal aortitis. This is rare but may be life threatening. The negative abdominal ultrasound and blood cultures make this unlikely. Syphilis is highly unlikely here but historically was an important cause of PUO. Kikuchi disease a disease of unknown aetiology is assocated with PUO and cervital lymphadenopathy occuring in Asian children. The age and the absense of lymphadenopathy make this unlikely here. Kikuchi-Fujimoto disease is another PUO associated with cervital lymphadenopathy that affects young women of Asian origin. The ethic origin of the patient here is not given. It can mimic SLE and is not an easy diagnosis. Mortality is ~2%. Other uncommon conditions in the differential diagnosis listing for PUO include: Castleman's disease, granulomatous hepatitis, inflammatory pseudotumour, Langerhan cell histiocytosis, Takayasu's arteritis, phenytoin hypersensitivity syndrome, preleukemia/myelodysplastic syndrome, habitual hyperthermia, hemophagocytotic syndrome,peritoneal mesothelioma, littoral cell angioma of the spleen, subacute thyroiditis, atypical neuroleptic malignant syndrome and parathyroid apoplexy. I do not feel competent to comment on these but someone else may wish to step up to the plate here. Competing interests: None declared |
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